Effects of joint mobilisation to improve dorsiflexion range of motion in female team sports athletes

Introduction: Ankle sprain is the most common injury on the active population and accounts for 22% of all sports injuries [1]. Although often considered an innocuous injury it is well documented that up to 80% of all people with a history of previous ankle sprain develop residual symptoms. This can include ligament laxity, loss of proprioception, instability and a decreased range of motion (ROM), particularly during dorsiflexion (DF-ROM) [2]. Joint mobilisation techniques that target the anterior-to-posterior movement of the talus are purported to increase dorsiflexion range of motion (DF-ROM) through the restoration of accessory or arthrokinematics movements that occur between the joint surfaces. Although joint mobilisations are informed by a conceptual framework of clinical reasoning, there is a lack of consensus within the literature regarding their effectiveness as a clinical technique. Indeed, there is a paucity of methodologically rigorous research into the interaction between treatment dose and ROM improvements [3]. The purpose of this study was to examine the effect of different treatment durations of a grade IV anteroposterior talocrural joint mobilisation on DF-ROM during a 2-week treatment intervention.
Methods: Twenty-four female team sports athletes (age = 23.0 ±5.7 years) participated in the study. All participants presented with a history of ankle instability which was confirmed using the Cumberland Ankle Instability Tool (CAIT), where a score of less than 24 was used to indicate the presence of the condition. Participants were randomly assigned to one of three treatment conditions (30 seconds, 60 seconds, or 120 seconds), and received six treatments over a 2-week period. DF-ROM was measured prior to the first and sixth treatment sessions using a digital goniometer (Digital Absolute + Axis Goniometer, Fabrication Enterprises Inc, USA) with the knee at 90 degrees of flexion. ANCOVA was used to test for differences in DF-ROM from the initial measure to post treatment, and between treatment groups. Effect size statistics were calculated using Cohen’s d.
Results: Mean (± SD), and absolute and percentage change scores for DF-ROM for each treatment duration are presented in Table 1. Statistical analysis revealed a significant improvement in DF-ROM following all mobilisation treatment durations (p < 0.001). An interaction effect was observed with each treatment duration being significantly different from each other from the initial to post treatment measurement (p < 0.001). Further analysis showed that increases in treatment duration were associated with statistically significant improvements in DF-ROM (p < 0.001). Effect size statistics showed that there was a ‘very large’ effect for the 120 second treatment group (d = 2.35), whilst a ‘large’ and ‘moderate’ effect size was evident for the 60 second (d = 0.87) and 30 second (d = 0.65) treatment groups respectively.
Conclusions: These results indicate that a joint mobilisation intervention that targets posterior talar glide is able to improve measures of DF-ROM in females with CAI, whilst increases in treatment duration confer greater improvements in DF-ROM within this population. Consequently, longer treatment durations should be incorporated when the objective is to increase an athletes ankle range of motion.