The Immediate Effects of Two Manual Therapy Techniques on Ankle Musculoarticular Stiffness and Dorsiflexion Range of Motion in People With Chronic Ankle Rigidity: A Randomized Clinical Trial

Increased musculoarticular stiffness (MAS) of the talocrural joint is a frequently encountered problem, identified during evaluation of weight bearing ankle dorsiflexion (WBADF). Such stiffness may follow ankle injury such as ankle sprain. In such a situation, MAS could be increased and might leads to a lack of joint flexibility as well as decreased dorsiflexion range-of-motion (ROM), however asymmetric rigidity does not necessarily always follow ankle sprain. Nevertheless, MAS is an important and necessary component of normal stability of the talocrural joint and could help to prevent abnormal ankle joint movement and ankle sprains.

Measurement of MAS can be determined by a technique known as free-oscillation, which is a comprehensive measure of joint stiffness comprising the stiffness of the muscle-tendon unit, skin, ligaments and joint capsule, along with a number of other mechanical and neuromuscular factors. The assessment of MAS is important when evaluating muscular performance, injury prevention and gender differences in flexibility. For example, men, as well as older people, are known to present with greater MAS than women and young people.

MAS of the talocrural joint can be objectively measured using an electromechanical device that imparts a passive oscillatory dorsiflexion movement, but also by means of clinical tests such as toe-wall distance and angular goniometric measurement during the weight bearing lunge test. Electromechanical measurement of ankle MAS has been used in several previous studies of asymptomatic participants and in patients with fibromyalgia syndrome, and spasticity after a stroke.

In orthopaedic manual therapy, different methods have been proposed to treat MAS associated with loss of dorsiflexion ROM at the talocrural joint. These include single session of Mulligan's Mobilization with Movement (MWM), anteroposterior mobilization of the talus, high velocity thrust, and Osteopathic Mobilization (OM). These methods have been described in clinical practice manuals, with greater proportion of studies reporting on the effects of MWM in comparison to high velocity thrust for improving ankle dorsiflexion ROM in chronic ankle instability or to study MWM efficacy in isolation for subacute or recurrent ankle sprains and for chronic ankle instability. With the exception of one study the results are generally in favor of MWM.

Generally MWM is an increasingly popular form of manual therapy for musculoskeletal disorders, concerning the ankle MWM try to improve talocrural ROM. MWM is a combination of accessory joint glide of the talus combined with active ankle dorsiflexion movement. The patient performs active WBADF while the therapist simultaneously applies an anteroposterior glide of the talus with respective posteroanterior tibial glide with the aid of a manual therapy belt. OM is a purely passive anteroposterior mobilization of the talus with respect to tibia, performed in a non weight-bearing position. To date, there have been no studies comparing the effectiveness of each technique with respect to electromechanically determined ankle MAS or ankle joint ROM determined by the WBADF lunge test.