A couple of weeks ago, I discussed the differential diagnosis of symptoms in relation to shoulder impingement syndrome (SIS). Amongst the research I referenced was the recent consensus paper that was published following the 2013 "Scapular Summit" in Kentucky.
The consensus, summarises the available research nicely in concluding that SIS is a complex, multifactorial pathology that requires further research. Consequently, just as with the selection of diagnostic tests for establishing the contributing factors to the pathology, the theories & opinions presented regarding the critical components to include in the management & rehabilitation of SIS are extensive.
Given the interest I received in response to the original article on shoulder assessment, I figured that a review of the recently published research conducted in regards to the various approaches to treatment of SIS would be a useful follow-up.
Whilst it is not the only proposed schematic for a structured assessment to establish a differential diagnosis of symptoms related to SIS (also see Lewis, 2008), the algorithm that Dr. Ann Cools proposed in relation to the diagnostic process provided the basis for the first blog & as a result the subsequent algorithm Cools constructed to establish a structure for the rehabilitation of SIS seems to be a consistent approach to adopt.
Given the strength of the research available highlighting the relationship between shoulder pain & scapular dyskinesis, the algorithm deconstructs the approach to treating shoulder pathology with a focus on the scapula rhythm as the centre point of the process.
 shoulder rehabilitation algorithm.jpg)
This post will concentrate on the left hand flow of the algorithm, addressing the lack of soft-tissue flexibility, whilst the next post will discuss the research available on the lack of muscle performance.
A constantly reported finding in relation to overhead athletes is an increased glenohumeral joint external rotation accompanied by a relatively reduced internal rotation range at the same joint, which is readily demonstrated when the scapula is stabilised on examination.
There are many theories that are offered as to the causes of these adaptations, which generally focus on the tightness of the posterior capsule, stiffness of the muscle tendon unit of the rotator cuff, along with a unilateral humeral retroversion. In addition, an increase in humeral head translation, potentially related to a shortening of the pectoralis minor in these athletes, has been linked to these pathological movement patterns (Crockett et al, 2002; Ellenbecker & Cools, 2010; Tyler et al, 2000).
Cools' algorithm combines the pectoralis minor, levator scapulae & rhomboids in one collective described as the "scapular muscles", which she suggests may "restrict normal scapula movement" should they become adaptively inflexible.
Borstad & Ludewig (2005) assessed scapular orientation & pectoralis minor length in 50 individuals, postulating that shortened muscle lengths would correspond to altered scapular movement patterns.
The results demonstrated portrayed interaction effects, with those individuals identified as having shortened pec minor length demonstrating scapulae positions that remained anteriorly tipped at higher angles of arm elevation. Meanwhile, the same individuals demonstrated significantly more internally rotated scapulae at lower arm elevations in the coronal plane.
A recent study conducted by Williams et al (2013) to evaluate the comparative effects of two different pec minor stretches (one gross & one specific technique) on a group of collegiate swimmers, proved unsuccessful in improving the upward rotation, external rotation or posterior tilt of the scapula with either method.
The gross stretch was achieved with the therapist fixing on the contralateral coracoid, then applying a horizontal abduction force through the subject's shoulder, whilst a more specific stretch was achieved by fixing the humeral head & scapula with one hand, whilst applying a tensile force to the muscle with the fingers & thumb of the opposite hand. Both techniques were held for a period of 30 seconds, followed by a 30 second rest period & a repeated stretch of the same duration.
Given that scapular dyskinesis is associated with chronic shoulder pain presentations, however, it is not surprising that an isolated stretch was deemed unsuccessful. There was no associated attempt to change scapular kinematics with proprioceptive exercises, strengthening protocol or indeed by employing joint or connective tissue mobilisation techniques beyond the simple passive stretch techniques. Subsequently, it is within reason to discount the studies negative findings as incidental given that such a practice would never be adopted in clinical practice.
Furthermore, Kromer et al's (2009) systematic review of the physiotherapy techniques adopted in the treatment of shoulder impingement syndrome concluded that whilst physiotherapy programmes that included active exercise & home exercise programmes could have a positive influence on symptoms of the condition, passive techniques alone had no significant benefit.
Other studies that have attempted to evaluate the benefits of stretching techniques on changing scapular orientation have looked at repetitive stretch bouts sustained for 15 minutes (Cools et al, 2013) & repeated on a daily basis either once or twice a day for 12 weeks (Aldridge et al, 2012; Litchfield, 2013; Holmgren et al, 2012). However, none of these studies have attempted to evaluate the benefits of their specific muscle stretching techniques in isolation, which given our clinical reasoning as sports physiotherapists, makes perfect sense in a clinical setting.
Whilst it is relatively easy to stretch pec minor in relative isolation of other muscles affecting scapular orientation, it is relatively difficult to isolate rhomboids without influencing the collective of "glenohumeral muscles & capsule" as described by Cools (2013) in her rehabilitation algorithm.
The cross-body stretch is deemed a good method of targeting the rhomboids when conducting the stretch without therapist assistance. Harshbarger et al (2013) recommend this technique but also advocate combining it with a therapist performing a posterior glenohumeral joint mobilisation in order to achieve greater glenohumeral internal rotation. This approach is supported by Cools et al (2012) when seeking to restore a decreased internal rotation range in the joint. In fact the latter study recommends incorporating the strategy into a prophylactic routine to reduce the risk of sustaining pathology in the overhead athlete.
In a similar approach, the sleeper stretch is promoted by several authors as a means of increasing the internal rotation at the glenohumeral joint, by directing a stretch to the posterior capsule. Again combining the stretch with a therapist-applied mobilisation in the form of a caudal translation applied through the elbow has been shown to improve the outcome (Jaggi & Lambert, 2010). However, whilst observing improvements in joint range, some have questioned the clinical significance of this approach (Laudner et al, 2008).
Tyler et al (2010) compared changes in internal rotation, external range of movement & posterior shoulder tightness between patients with complete resolution of symptoms versus patients with residual symptoms & concluded that the resolution of symptoms was related to the correction of posterior shoulder tightness but not to the correction of glenohumeral joint internal rotation alone.
One muscle that does appear to get overlooked in much of the literature in relation to the scapular function is teres major. In throwers, the teres major can become short & tight from the demands of accelerating the arm through adduction & internal rotation (Urbin et al, 2012). Subsequently, the scapular has to increase its upward rotation as the true range decreases with the adaptive shortening of the muscle.
To direct a stretch to the teres major, the athlete must abduct, flex & externally rotate the glenohumeral joint, with a more specifically directed mobilisation achieved by a physiotherapist fixing the scapula to prevent upward rotation.
Once the rehabilitation plan has considered the issues in relation to flexibility, the right side of the algorithm can then be addressed & the programme completed by adding in the muscle performance components of muscle control & muscle strength.
My next blog will look at the current research available to guide the sports physiotherapist through this aspect of the management.
