Effect of Limited Ankle Dorsiflexion on Lower Limbs and Trunk Kinematics During Squatting.

OBJECTIVE

The purpose of this observational study was to examine whether limited ankle dorsiflexion (LAD) affects the kinematic parameters of the lower limb joints and trunk during a bilateral squat.

METHODS

Forty-four physically active and non-injured participants, with limited ankle dorsiflexion (DF) < 30° (n = 18) and without limitations, DF > 35° (n = 26) during the weight-bearing lunge test, were recruited. The angles and ranges of motion (ROM) of lower limb joints, pelvis and spine were recorded using a 3D motion capture system.

RESULTS

Participants with LAD had a greater pelvis ROM in the sagittal plane (P = .001), a greater hip and lumbar spine flexion ROM (P = .002; P = .01, respectively) and a greater trunk forward lean (P < .001) during squatting compared to the control group. In the LAD group, ankle DF during squatting correlated with trunk lean (r = -0.49, P = .04), while in the control group, it correlated with spine mobility (r = 0.44, P = .03).

CONCLUSIONS

The findings suggest that the pelvis and trunk forward lean have a regulatory role in response to LAD during squatting.