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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

Segmental motor strategy variables derived from global motor strategy variables. A: Examples (mean profiles ±1 standard deviation) for a typical participant of different contributions of the pelvis and trunk lowering to the global CoM lowering between AM and PM directions in the central phase. B: Contribution of segmental strategy variables to the global CoM lowering represented by beta standardized coefficients (β) for each reaching direction and each lower limb. Each bar graph represents a combination of the dominant limb of the healthy group with either the uninjured limb (D-UI limb) or the injured limb (D-I limb) of the LAS group (n = 20). C: Hip ADD angular velocities of the reaching limb for the injured limb (dotted line) and the control group (black line and shaded area; mean ± 1 standard deviation) in each direction and a summary (mean velocity ±1 SD) at three different time points in the central phase for the medial direction. Asterisks represent a significant difference between groups (MANOVA; p < 0.05).
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Fig3: Segmental motor strategy variables derived from global motor strategy variables. A: Examples (mean profiles ±1 standard deviation) for a typical participant of different contributions of the pelvis and trunk lowering to the global CoM lowering between AM and PM directions in the central phase. B: Contribution of segmental strategy variables to the global CoM lowering represented by beta standardized coefficients (β) for each reaching direction and each lower limb. Each bar graph represents a combination of the dominant limb of the healthy group with either the uninjured limb (D-UI limb) or the injured limb (D-I limb) of the LAS group (n = 20). C: Hip ADD angular velocities of the reaching limb for the injured limb (dotted line) and the control group (black line and shaded area; mean ± 1 standard deviation) in each direction and a summary (mean velocity ±1 SD) at three different time points in the central phase for the medial direction. Asterisks represent a significant difference between groups (MANOVA; p < 0.05).

Mentions: As the majority of the LAS participants (70%) had injured their dominant limb, performance and strategy variables in all test conditions of the LAS participants were compared, for the second research objective, to those obtained from the dominant limb of the healthy group. A bar graph representing all regression coefficient combinations was used to compare each component’s contributions to global lowering for each reaching direction (see Figure 3, Objective 2). Peak-to-peak angular velocities in the stance limb were compared through multivariate analyses to measure the group and limb effects (Objective 1). The hip abduction velocity of the reaching limb was analysed at three times of measure (25, 50 and 75% of the central phase duration) to look for potential group effects for the injured and the uninjured limbs (repeated measured ANOVA) (Objective 1).Figure 3


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)

Segmental motor strategy variables derived from global motor strategy variables. A: Examples (mean profiles ±1 standard deviation) for a typical participant of different contributions of the pelvis and trunk lowering to the global CoM lowering between AM and PM directions in the central phase. B: Contribution of segmental strategy variables to the global CoM lowering represented by beta standardized coefficients (β) for each reaching direction and each lower limb. Each bar graph represents a combination of the dominant limb of the healthy group with either the uninjured limb (D-UI limb) or the injured limb (D-I limb) of the LAS group (n = 20). C: Hip ADD angular velocities of the reaching limb for the injured limb (dotted line) and the control group (black line and shaded area; mean ± 1 standard deviation) in each direction and a summary (mean velocity ±1 SD) at three different time points in the central phase for the medial direction. Asterisks represent a significant difference between groups (MANOVA; p < 0.05).
© Copyright Policy - open-access
Related In: Results  -  Collection

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

Fig3: Segmental motor strategy variables derived from global motor strategy variables. A: Examples (mean profiles ±1 standard deviation) for a typical participant of different contributions of the pelvis and trunk lowering to the global CoM lowering between AM and PM directions in the central phase. B: Contribution of segmental strategy variables to the global CoM lowering represented by beta standardized coefficients (β) for each reaching direction and each lower limb. Each bar graph represents a combination of the dominant limb of the healthy group with either the uninjured limb (D-UI limb) or the injured limb (D-I limb) of the LAS group (n = 20). C: Hip ADD angular velocities of the reaching limb for the injured limb (dotted line) and the control group (black line and shaded area; mean ± 1 standard deviation) in each direction and a summary (mean velocity ±1 SD) at three different time points in the central phase for the medial direction. Asterisks represent a significant difference between groups (MANOVA; p < 0.05).
Mentions: As the majority of the LAS participants (70%) had injured their dominant limb, performance and strategy variables in all test conditions of the LAS participants were compared, for the second research objective, to those obtained from the dominant limb of the healthy group. A bar graph representing all regression coefficient combinations was used to compare each component’s contributions to global lowering for each reaching direction (see Figure 3, Objective 2). Peak-to-peak angular velocities in the stance limb were compared through multivariate analyses to measure the group and limb effects (Objective 1). The hip abduction velocity of the reaching limb was analysed at three times of measure (25, 50 and 75% of the central phase duration) to look for potential group effects for the injured and the uninjured limbs (repeated measured ANOVA) (Objective 1).Figure 3

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