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Alteration in global motor strategy following lateral ankle sprain.

Bastien M, Moffet H, Bouyer LJ, Perron M, Hébert LJ, Leblond J - BMC Musculoskelet Disord (2014)

Bottom Line: The global body centre of mass variables were significantly correlated to SEBT performance (MRD).Modifications in global motor strategies were found in participants with LAS as well as a decreased performance on the SEBT for the injured and uninjured lower limbs.These results support the hypothesis that following LAS, there may be a maladaptive reorganization of the central motor commands. 3b.

View Article: PubMed Central - PubMed

Affiliation: Faculty of Medicine, Rehabilitation Department, Laval University, Quebec, QC, Canada. Helene.Moffet@rea.ulaval.ca.

ABSTRACT

Background: Lateral ankle sprain (LAS) has often been considered an injury leading to localized joint impairments affecting the musculoskeletal system. Persistent chronic ankle instability and bilateral alterations in motor control after a first ankle sprain episode suggest that the origin of relapses might be a maladaptive reorganization of central motor commands. The objectives of this study were (1) to compare the quality of motor control through motor strategy variables of two groups (with and without LAS) from a military population (n = 10/group), (2) to evaluate the contribution of the lower limbs and the trunk to global body strategy and (3) to identify which global variable best estimates performance on the Star Excursion Balance Test (SEBT) for each group, reaching direction, and lower limb.

Methods: Personal and clinical characteristics of the participants of both groups were collected. Their functional ability was measured using questionnaires and they performed a series of functional tests including the SEBT. During this test, the maximal reach distance (MRD) and biomechanical data were collected to characterize whole body and segmental strategies using a 3D motion capture system.

Results: At maximal lower limb reach, participants with LAS had a smaller variation in their vertical velocity in lowering-straightening and lowered the body centre of mass less for all injured limb conditions and some conditions with the uninjured lower limb. The global body centre of mass variables were significantly correlated to SEBT performance (MRD).

Conclusion: Modifications in global motor strategies were found in participants with LAS as well as a decreased performance on the SEBT for the injured and uninjured lower limbs. These results support the hypothesis that following LAS, there may be a maladaptive reorganization of the central motor commands.

Level of evidence: 3b.

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Related in: MedlinePlus

Global body strategies along the vertical axis (A) and horizontal plane (C) in the central phase. A: the profiles for global CoM lowering (#) and for the peak-to peak velocity of the global CoM (# #) are illustrated for one limb of both groups (mean ± 1 standard deviation for healthy group and mean for LAS group; n = 10 trials per group) during the medial reaching direction on the SEBT. B: mean values (+1 standard deviation) for global CoM lowering and peak-to peak of CoM vertical velocity of both groups. C: CoM displacement in the horizontal plane (# # #) during the different conditions (directions and limbs) in both groups. Horizontal resultant lines of global CoM position at foot contact (doted circles) were calculated and used for further statistical analyses. D: mean values (+1 standard deviation) for global CoM in the horizontal plane. Asterisks in figures B and D represent a significant difference between groups (MANOVA; p < 0.05; n = 20 limbs per group).
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Fig2: Global body strategies along the vertical axis (A) and horizontal plane (C) in the central phase. A: the profiles for global CoM lowering (#) and for the peak-to peak velocity of the global CoM (# #) are illustrated for one limb of both groups (mean ± 1 standard deviation for healthy group and mean for LAS group; n = 10 trials per group) during the medial reaching direction on the SEBT. B: mean values (+1 standard deviation) for global CoM lowering and peak-to peak of CoM vertical velocity of both groups. C: CoM displacement in the horizontal plane (# # #) during the different conditions (directions and limbs) in both groups. Horizontal resultant lines of global CoM position at foot contact (doted circles) were calculated and used for further statistical analyses. D: mean values (+1 standard deviation) for global CoM in the horizontal plane. Asterisks in figures B and D represent a significant difference between groups (MANOVA; p < 0.05; n = 20 limbs per group).

Mentions: The SEBT task was divided into two main subtasks: the going-to- and the return-from-MRD (Figure 1A). The transition between these subtasks has been called the central phase and was defined as -1 s to +1 s after foot contact (Figure 1: central grey rectangle). Four variables describing the behaviour of the CoMgl, called global variables, have been chosen as key indicators of global body strategy during this task. The maximal displacement of the CoMgl vertically; peak-to-peak CoMgl velocities along the vertical axis were calculated during the central phase (Figure 2A); distance between the centre of the foot and the mean position of the horizontal CoMgl when the foot contacted the floor and the horizontal excursion of the CoMgl during the central phase were also calculated (Figure 2C).Figure 2


Alteration in global motor strategy following lateral ankle sprain.

Bastien M, Moffet H, Bouyer LJ, Perron M, Hébert LJ, Leblond J - BMC Musculoskelet Disord (2014)

Global body strategies along the vertical axis (A) and horizontal plane (C) in the central phase. A: the profiles for global CoM lowering (#) and for the peak-to peak velocity of the global CoM (# #) are illustrated for one limb of both groups (mean ± 1 standard deviation for healthy group and mean for LAS group; n = 10 trials per group) during the medial reaching direction on the SEBT. B: mean values (+1 standard deviation) for global CoM lowering and peak-to peak of CoM vertical velocity of both groups. C: CoM displacement in the horizontal plane (# # #) during the different conditions (directions and limbs) in both groups. Horizontal resultant lines of global CoM position at foot contact (doted circles) were calculated and used for further statistical analyses. D: mean values (+1 standard deviation) for global CoM in the horizontal plane. Asterisks in figures B and D represent a significant difference between groups (MANOVA; p < 0.05; n = 20 limbs per group).
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4300726&req=5

Fig2: Global body strategies along the vertical axis (A) and horizontal plane (C) in the central phase. A: the profiles for global CoM lowering (#) and for the peak-to peak velocity of the global CoM (# #) are illustrated for one limb of both groups (mean ± 1 standard deviation for healthy group and mean for LAS group; n = 10 trials per group) during the medial reaching direction on the SEBT. B: mean values (+1 standard deviation) for global CoM lowering and peak-to peak of CoM vertical velocity of both groups. C: CoM displacement in the horizontal plane (# # #) during the different conditions (directions and limbs) in both groups. Horizontal resultant lines of global CoM position at foot contact (doted circles) were calculated and used for further statistical analyses. D: mean values (+1 standard deviation) for global CoM in the horizontal plane. Asterisks in figures B and D represent a significant difference between groups (MANOVA; p < 0.05; n = 20 limbs per group).
Mentions: The SEBT task was divided into two main subtasks: the going-to- and the return-from-MRD (Figure 1A). The transition between these subtasks has been called the central phase and was defined as -1 s to +1 s after foot contact (Figure 1: central grey rectangle). Four variables describing the behaviour of the CoMgl, called global variables, have been chosen as key indicators of global body strategy during this task. The maximal displacement of the CoMgl vertically; peak-to-peak CoMgl velocities along the vertical axis were calculated during the central phase (Figure 2A); distance between the centre of the foot and the mean position of the horizontal CoMgl when the foot contacted the floor and the horizontal excursion of the CoMgl during the central phase were also calculated (Figure 2C).Figure 2

Bottom Line: The global body centre of mass variables were significantly correlated to SEBT performance (MRD).Modifications in global motor strategies were found in participants with LAS as well as a decreased performance on the SEBT for the injured and uninjured lower limbs.These results support the hypothesis that following LAS, there may be a maladaptive reorganization of the central motor commands. 3b.

View Article: PubMed Central - PubMed

Affiliation: Faculty of Medicine, Rehabilitation Department, Laval University, Quebec, QC, Canada. Helene.Moffet@rea.ulaval.ca.

ABSTRACT

Background: Lateral ankle sprain (LAS) has often been considered an injury leading to localized joint impairments affecting the musculoskeletal system. Persistent chronic ankle instability and bilateral alterations in motor control after a first ankle sprain episode suggest that the origin of relapses might be a maladaptive reorganization of central motor commands. The objectives of this study were (1) to compare the quality of motor control through motor strategy variables of two groups (with and without LAS) from a military population (n = 10/group), (2) to evaluate the contribution of the lower limbs and the trunk to global body strategy and (3) to identify which global variable best estimates performance on the Star Excursion Balance Test (SEBT) for each group, reaching direction, and lower limb.

Methods: Personal and clinical characteristics of the participants of both groups were collected. Their functional ability was measured using questionnaires and they performed a series of functional tests including the SEBT. During this test, the maximal reach distance (MRD) and biomechanical data were collected to characterize whole body and segmental strategies using a 3D motion capture system.

Results: At maximal lower limb reach, participants with LAS had a smaller variation in their vertical velocity in lowering-straightening and lowered the body centre of mass less for all injured limb conditions and some conditions with the uninjured lower limb. The global body centre of mass variables were significantly correlated to SEBT performance (MRD).

Conclusion: Modifications in global motor strategies were found in participants with LAS as well as a decreased performance on the SEBT for the injured and uninjured lower limbs. These results support the hypothesis that following LAS, there may be a maladaptive reorganization of the central motor commands.

Level of evidence: 3b.

Show MeSH
Related in: MedlinePlus