Is the inverted surface landing more suitable in evaluating ankle braces and ankle inversion perturbation?

OBJECTIVE

To investigate biomechanical (kinematic) differences between 2 ankle brace testing protocols: landing on an inverted surface (IS) and inversion drop on an inversion platform.

DESIGN

Five trials in each of 4 dynamic movement conditions were performed: inversion drop and drop landing from 0.45 m onto an IS without and with an ankle brace. A 7-camera motion analysis system was used to obtain the 3-dimensional kinematics. A 2 × 2 (brace × movement) repeated measures analysis of variance was used to evaluate selected variables for inversion drop and IS landing.

SETTING

Research laboratory.

PATIENTS

Eleven healthy subjects participated in the study.

INTERVENTIONS

None.

MAIN OUTCOME MEASURES

Maximum ankle frontal plane and sagittal plane joint angles, range of motion, and maximum angular velocity.

RESULTS

The IS landing resulted in significantly earlier maximum inversion, inversion velocities, dorsiflexion range of motion (ROM), contact dorsiflexion velocity, and maximum dorsiflexion velocity compared with the inversion drop. The ankle brace application during the IS landing reduced the contact plantarflexion angle, dorsiflexion ROM and maximum dorsiflexion velocity, and maximum inversion.

CONCLUSIONS

The results from this study showed that the IS landing protocol produced significantly earlier maximum inversion angle and velocity and inversion velocities compared with the inversion drop protocol. These results showed that the IS landing is more demanding and should be considered in future investigations of ankle braces and lateral ankle performance/injury mechanisms.