Immediate combined effect of gastrocnemius stretching and sustained talocrural joint mobilization in individuals with limited ankle dorsiflexion: A randomized controlled trial

Highlights

• We examined combined effect of stretching and talocrural joint mobilization.

• Combination of both interventions increased ankle dorsiflexion during gait.

• Combination of both interventions increased time to heel-off during gait.

• General gastrocnemius stretching did not change ankle kinematics during gait.

• Combination of both interventions is useful to improve ankle kinematic during gait.

Abstract

Background

Although gastrocnemius stretching and talocrural joint mobilization have been suggested as effective interventions to address limited ankle dorsiflexion passive range of motion (DF PROM), the effects of a combination of the two interventions have not been identified.

Objective

The aim of the present study was to compare the effects of gastrocnemius stretching combined with joint mobilization and gastrocnemius stretching alone.

Design

A randomized controlled trial.

Methods

In total, 24 individuals with limited ankle DF PROM were randomized to undergo gastrocnemius stretching combined with joint mobilization (12 feet in 12 individuals) or gastrocnemius stretching alone (12 feet in 12 individuals) for 5 min. Ankle kinematics during gait (time to heel-off and ankle DF before heel-off), ankle DF PROM, posterior talar glide, and displacement of the myotendinous junction (MTJ) of the gastrocnemius were assessed before and after the interventions. The groups were compared using two-way repeated measures analysis of variance.

Results/findings

: Greater increases in the time to heel-off and ankle DF before heel-off during gait and posterior talar glide were observed in the stretching combined with joint mobilization group versus the stretching alone group. Ankle DF PROM and displacement of the MTJ of the gastrocnemius were increased significantly after the interventions in both groups, with no significant difference between them.

Conclusions

These findings suggest that gastrocnemius stretching with joint mobilization needs to be considered to improve ankle kinematics during gait.

Introduction

To prevent and manage lower extremity injuries, it is essential to have sufficient ankle dorsiflexion passive range of motion (DF PROM), with at least 10° of ankle DF PROM with the knee extended (Gross, 1995, Donatelli and Wooden, 1996, Sahrmann, 2010). It has been reported that limited ankle DF PROM is a risk factor for lower extremity injuries (Kibler et al., 1991, Pope et al., 1998, Schepsis et al., 2002, Willems et al., 2005). Also, limited ankle DF PROM contributes to compensatory movements during gait including early heel-off, subtalar joint pronation, and midtarsal joint DF (Gross, 1995, Donatelli and Wooden, 1996, Karas and Hoy, 2002), which increases loading duration on the forefoot and contributes to a hypermobile midfoot (Dananberg et al., 2000, Karas and Hoy, 2002). Because excessive stresses on the foot and ankle complex caused by compensatory movements are cumulative during functional activities, it is believed that such compensatory movements contribute to pain in the foot and ankle complex (Dananberg et al., 2000, Tabrizi et al., 2000, Karas and Hoy, 2002, Schepsis et al., 2002).

Compensatory movements caused by limited ankle DF PROM are apparent during gait, especially in the mid-stance phase (Gross, 1995, Johanson et al., 2006a, Johanson et al., 2006b, Drewes et al., 2009, Johanson et al., 2009). Limited ankle DF PROM disturbs tibial advancement over the foot during the mid-stance phase, and consequently an early heel-off strategy is adopted to progress the body over the foot during the stance phase of gait (Karas and Hoy, 2002, Perry and Burnfield, 2010, Sahrmann, 2010). Ultimately, early heel-off, together with insufficient tibial advancement, increases stress on the forefoot throughout the increased time of weight-bearing and pressure on the forefoot (Dananberg et al., 2000, Yoon et al., 2014), which may affect foot and ankle injuries (Kibler et al., 1991, Wilder and Sethi, 2004). From this viewpoint, intervention to increase ankle DF together with time to heel-off during the stance phase of gait should be considered when designing intervention programs for individuals with limited ankle DF PROM.

Gastrocnemius stretching exercises are often performed to increase ankle DF PROM with the knee extended (Dinh et al., 2011, Nakamura et al., 2011). Gastrocnemius stretching exercises lead to greater ankle DF PROM with the knee extended because of increased tolerance to stretching, modification in sensation (Weppler and Magnusson, 2010), and changes in the architecture of the gastrocnemius muscle-tendon unit, especially in the displacement of the myotendinous junction (MTJ) of the gastrocnemius (Morse et al., 2008, Nakamura et al., 2011, Mizuno et al., 2013). A previous study using ultrasonography identified decreased muscle stiffness, together with increased displacement of the MTJ of the gastrocnemius, after 5 min of gastrocnemius stretching (Nakamura et al., 2011). However, no significant difference in ankle DF before heel-off or time to heel-off was found after gastrocnemius stretching (Johanson et al., 2006b, Johanson et al., 2009), despite significant increases in ankle DF PROM and displacement of the MTJ of the gastrocnemius (Morse et al., 2008, Nakamura et al., 2011).

To correct compensatory movements during gait, interventions in addition to general gastrocnemius stretching should be considered. Because limited ankle DF PROM with the knee extended may result from gastrocnemius tightness and/or inadequate accessory motion of the talocrural joint (Hubbard and Hertel, 2006, Sahrmann, 2010), talocrural joint mobilization may be such an appropriate additional intervention. Previous studies found significant increases in the amount of posterior talar glide and ankle DF PROM after sustained anterior-to-posterior talocrural joint mobilization with movement (Vicenzino et al., 2006). Additionally, the force provided by sustained anterior-to-posterior talocrural joint mobilization fixes the talus at the end-range of the posterior talar glide, and such stabilization force consequently facilitates relative tibial advancement over the fixed foot during closed-chain activities (Sahrmann, 2010, Kang et al., 2014).

Considering the influences of gastrocnemius stretching (Dinh et al., 2011) and talocrural joint mobilization (Vicenzino et al., 2006), the combined use of both interventions may lead to greater improvement in the ankle DF PROM and gait patterns. However, no reported study has examined the combined effect of both interventions. Thus, the aim of the present study was to compare the effects of gastrocnemius stretching combined with sustained talocrural joint mobilization and gastrocnemius stretching alone in individuals with limited ankle DF PROM with the knee extended.