Effect duration of a self-applied talocrural joint mobilization on restricted dorsiflexion: a repeated measures design.

Objectives: We aimed to determine the effect duration of a talocrural mobilization on individuals with restricted dorsiflexion during a static weight bearing lunge test (WBLT) and dynamic 3D motion capture-based peak ankle dorsiflexion during a forward step down (FSD) task. Secondarily, we aimed to correlate any immediate changes in ankle mobility with concurrent changes in proximal joint kinematics during the FSD post-mobilization.

Methods: Seventy-six individuals were screened for dorsiflexion restriction, of which 26 (15 females, 22.3 ± 2.2 years old, body mass index 25.2 ± 2.9 kg/m2) qualified with a WBLT of ≤ 35° on at least one limb. A baseline WBLT measure and 3D motion capture of 5 consecutive FSD repetitions on a 6-inch box were obtained. Participants then viewed an instructional video of a talocrural joint self-mobilization using a resistance band. WBLT and FSD were collected again immediately post-mobilization and at 5-min intervals for 60 min or until the WBLT returned to baseline for 2 consecutive measures.

Results: WBLT dorsiflexion showed a mean increase of 6.5 degrees (p < 0.001) post-mobilization. The effect faded over time and no longer differed from baseline 25 min post-mobilization (p = 0.964). Dynamic peak ankle dorsiflexion did not change post-mobilization at any time point (p ≥ 0.546). No 3D kinematic time-course changes were observed at the hip or knee. However, immediate raw alterations in dorsiflexion correlated with alterations for hip and knee flexion.

Discussion/conclusion: A talocrural joint mobilization increased static dorsiflexion per the WBLT for a 20-25-min period with regression to baseline. However, increased dynamic ankle dorsiflexion was not observed during the FSD task. Improved mobility alone does not appear to change movement patterns. Clinicians should be aware of both effect duration and the potential need for task-specific training to better facilitate dynamic utilization of increased mobility.