Ankle sprain is considered as the most common injury occurring in the active population.¹ All patients with the history of previous ankle sprain developed symptoms such as decreased range of motion of dorsiflexion, laxity of ligaments, loss of proprioception, pain during activity, swelling and also the feeling of “giving way” and ankle instability.¹ chronic ankle instability is defined by Hertel et al. as “repetitive bouts of lateral ankle instability resulting in numerous ankle sprains.”¹ Chronic ankle instability is also considered as a complex ankle disorder that was caused by mechanical instability, functional instability, or could be the combination of both the conditions.¹ Mechanical instability is objective and involves ankle joint movement beyond physiological range of motion, Whereas Functional instability is considered as the feeling of instability which is subjective in nature and is in relation with a proprioceptive neuromuscular dysfunction.¹ intrinsic and extrinsic are the predisposing factors that could lead to chronic ankle instability.¹ extrinsic factors are type of ground surface, types of footwear, physical activity. Intrinsic factors include ratio of increased ankle eversion to inversion strength, dorsiflexion to plantarflexion strength ratio, plantarflexion strength, dominance of limb, decreased ROM, postural control or lower leg alignment. Manual therapy approach tends to lengthen the joint capsule and ligaments associated with it by stretching them through accessory motion in order to restore dorsiflexion range of motion by increasing the extensibility of non-contractile tissues.  Mobilization with movement is considered effective in improving function, persistent instability feeling, ankle range of motion of dorsiflexion, reducing swelling and pain, improving function and postural control in patients suffered with lateral ankle sprains. Some of these symptoms are present together or individually in which conventional treatment has been inefficient. In chronic ankle instability it appears that functional and mechanical impairments co-exist. Muscle inhibition has been identified in the fibularis longus and soleus muscles in cases of functional instability of ankle.² Needle et al suggested that subjective instability might be related to deficits in muscle spindle function during mechanical loading of the ankle.² Pietrosimone et al concluded that alterations were seen in neuromuscular function post joint injury contributed to altered biomechanics affecting long term functional outcomes.2 Hence these studies are in support that there is presence of neuromuscular dysfunction in CAI.²

Strain counterstrain is an indirect osteopathic treatment which describes the theatrical mode of neuro-muscular skeletal dysfunction where a mechanical strain injury leads to changes in muscle spindle around the involved segment known as the proprioceptive theory. Based on this theory, during lateral ankle sprain the affected foot turns into inversion hence the spindles of invertor muscles adapt to a newly shortened muscle length.² The quick stretch and resulting contraction of the evertor muscles causes the invertor muscles to be quickly stretched from the adapted shortened position, leaving the invertor muscles in a state of increased neuromuscular hyperactivity with a facilitated spindle system. According to the proprioceptive theory, this scenario leaves the ankle in a state of neuro muscular skeletal dysfunction which in future leads to chronic ankle instability and hence repeated episodes of ankle sprains.

In strain counterstrain dysfunctional muscle groups are identified through localization of significant tender points which are defined as small zones of tense, tender, and edematous muscle  and fascial tissue about 1 cm in diameter and is 4 times more tender as compared to the normal tissue.²  authors like Stillwell and melzack [48] concluded that there may not be any significant difference  between SCS point and trigger point, a reduction in the tenderness degree of SCS tender point  is associate with a modification of body position. However, till date no assessment too is available which can assess SCS tender points.

The role of soleus and gastrocnemius muscle tightness has also been considered as the contributing factor for restriction of the range of motion of dorsiflexion nevertheless following the results obtained by Johanson in 2008, range of motion of  dorsiflexion seems to be more in relation with subtalar joint than muscle tightness.1 there are some manual therapy techniques which are based on talocrural joint mobilization which have proven the effectiveness of this kind of stimuli in postural control, ROM of dorsiflexion and improvement in arthrokinematic. [2,9,20,21] during dynamic balance tasks balance is usually altered in patients with chronic ankle instability, this seems to be because of deficit in neuromuscular control and proprioception of the ankle joint.

NEED FOR THE STUDY

Conventional physical therapy techniques such as electrotherapy, taping, etc has been shown good results in decreasing the edema and pain which is associated with ankle sprain.¹ nevertheless the improvement obtained with such therapies does not provide a remedy to the possible sequelae associated with sprain of ankles, such as muscle weakness, postural control deficits, nerve deficits, invertor  and evertor strength deficits, sensorimotor deficits, delayed peroneal muscle reaction time ,damage to ligamentous and capsular mechanoreceptors with dysfunction in the afferent–efferent mechanism, alterations in the dorsiflexion ROM of ankle joint, proprioception deficits, etc.^1,2 for these reasons it is important to make integral approaches in the treatment of ankle sprain in order to avoid its reoccurrence. It is estimated that about 70% re-sprain occurs after the previous episode of ankle sprain. After the onset of ankle sprain range of motion of dorsiflexion at the ankle joint is affected, this is considered as a predisposing factor of re-injury. Range of motion of Dorsiflexion at the ankle joint is associated with positional alteration of the talus in relation with the ankle mortise or an alteration in normal talar arthrokinematics, being a reduced posterior talar glide.1 Another factor for recurrent ankle sprain is the decreased balance. Mobilization of joint is effective in reducing predisposing factors to re-injury and whose improvement is hypothesized to be derived by the posterior talar glide alteration. Literature suggests that the stretching of articular which is occurring due to mobilization of joints tends to increase the sensory output of mechanoreceptors in ligaments and capsules due to the activation of gamma motor neurons by tissue traction which is related to improvement of postural control. MWM can be used in acute and sub-acute ankle sprains in weight bearing or non-weight bearing conditions with the particularity of patient moves actively.1

Lack of required strength, functional weakness, foot laxity, neuromuscular imbalance etc. are proven intrinsic risk factors for increase in chances chronic ankle instability, hence it is imperative to study the effects of passive MWM with strain counterstrain to achieve functional as well as mechanical stability in the ankle and thus treating the root cause of chronic ankle instability.

Research question

 What will be the effect of Strain Counter Strain With Passive MWM In Patients With Chronic Ankle Instability, in terms of postural control, ankle stability and dynamic balance?

Hypotheses

Null hypotheses (H₀)

There will be no effect in Strain Counter Strain With Passive MWM In Patients With Chronic Ankle Instability in terms of postural control and dynamic balance.

Alternate hypotheses (H₁)

There will be significant effect in Strain Counter Strain With Passive MWM In Patients With Chronic Ankle Instability, in terms of postural control and dynamic balance.