San Antonio, Texas, USA
Sunday 12th January 2014
My focus over the last month has been revising for my National Strength & Conditioning Association, CSCS exam, which goes some way towards explaining why my blog hasn't been updated since before Christmas.  

It has been a valuable process, revising aspects of my Exercise Physiology MSc, components of my Sports Physiotherapy MSc & knowledge gleaned from various additional courses that I have taken throughout my career.  In addition, working with the likes of Raph Brandon (recently appointed Director of Performance Solutions at the English Institute of Sport), James Moore (himself recently appointed Manager of the Intensive Rehabilitation Unit at the British Olympic Association), Mark Hulse, Richard Hawkins, Tony Strudwick & Gary Walker (all integral members of the Manchester United performance team) over the years has been instrumental in developing my fluency in the field.  I've had a very privileged upbringing, for sure!

I will sit my exams next week but in the meantime, I was delighted to be able to accept an invite to visit the San Antonio Spurs for a couple of days this week.  

The Texan franchise enjoys an interesting status...not necessarily the glory boys of the NBA (the Miami Heat, the LA Lakers & the Chicago Bulls would probably be more well known outside of the USA), the team boasts the honour of being the most successful of all American professional sports outfits competing over the last 20 years, with the New England Patriots coming in second in win percentage over that time.

It comes as no surprise that head coach, Gregg Popovich has been at the helm for 18 of those 20 years & he shares a reputation not dissimilar to Sir Alex Ferguson in the basketball fraternity.  Coach Popovic was the first to widely recruit from the international leagues & today the Spurs have the highest number of foreign players in the NBA.  Meanwhile, the ability of the team to peak in the post-season time & again is often attributed to "Pop's" ability to manage the load on his playing staff.

Add in a hugely supportive front office with a desire to operate at a consistently high standard, whilst maintaining significant continuity & you can see why the Spurs have won 4 Championships (& finished runners-up to Miami in last year's best of seven finale) since 1999.

Whilst now is not the time to go into detail about my visit to the Spurs, I will go as far as saying I have been made extremely welcome by everyone I have met since arriving.  Furthermore, I have been very impressed with the ethos & culture that is apparent from the moment you walk through the door.

To keep the basketball-related theme alive in the blog, I am going to discuss a clutch of papers that I have been reading on my journey from Princeton.  A week or so ago, I listened to a podcast broadcast by the British Journal of Sports Medicine, with Babette Pluim interviewing shoulder expert Dr. Ann Cools.  It was this talk that stimulated an afternoon of searching for & reviewing several related articles.

Ann Cools' work has been on my radar for nearly ten years now (particularly since my time working in rugby & tennis) & during this time, she has contributed greatly to the available evidence regarding shoulder impingement, scapular dyskinesis & the assessment of related risk factors in overhead athletes.  

Based out of the Rehabilitation Sciences & Physiotherapy Department at Ghent University in Belgium, Ann has also forged strong links with the Swedish tennis academy, who have been willing collaborators in her research.

The interview covers topics such as the involvement of the scapula in shoulder pain in overhead athletes, treatment strategies for shoulder impingement, eccentric training for the shoulder & whether scapula dyskinesis is the cause or consequence of shoulder injuries with an insidious onset.  It is well worth a listen & you can access it by clicking on the link below:

Subacromial impingement syndrome (SIS) is a frequently encountered symptom in the sports physiotherapy world, especially when dealing with athletes competing in sports where overhead skills are required.  Personally, I have seen presentations in tennis players, rugby players, soccer goalkeepers, quarterbacks in American football, basketball players & lacrosse players but have also spoken to counterparts in Scandinavia where handball players comprise a substantial proportion of their cases.

The syndrome has a complex presentation & determining the causative factors can be a difficult task.  Scapular orientation & control, muscle imbalances, range of movement restrictions or soft tissue trauma may all play a role.

The first study I remember reading on SIS authored by Dr. Cools was published back in 2004.  Using a Biodex dynamometer in conjunction with EMG, the group looked at isokinetic force production & muscle activity of the trapezius muscles & serratus anterior during a protraction/retraction task, as performed by elite overhead athletes with impingement syndrome.

At high velocities, the results showed significant deficits in peak force production by the rotators during isokinetic protraction & significantly less EMG activity in the lower trapezius during retraction on the injured side in comparison with the non-injured side.  In addition the protraction:retraction peak force ratio at low velocities was significantly reduced on the injured side.  

This bears clinical relevance when you consider the important role that the serratus anterior plays during the acceleration phase of a throwing action, concentrically protracting the scapula as the arm is adducted & internally rotated.  The scapula must smoothly protract, initially laterally & then anteriorly around the thoracic wall in order to maintain a normal position relative to the humeral head.  A decrease in the peak force capabilities during this protraction may compromise the functional stability of the shoulder & result in a tensile overload of the glenohumeral joint.

Meanwhile, a systematic review of the available literature by Ratcliffe et al (2013) sought to establish whether or not a difference in scapular orientation exists between people with shoulder impingement syndrome & those without.

Around 7,500 abstracts were identified, with 10 satisfying criteria for inclusion.  The studies used 2 dimensional radiological measurements, 360 degree inclinometers or 3D motion & tracking devices to determine scapular position in their subjects.  The results were, however, inconsistent, with some authors reporting patterns of reduced upward rotation, increased anterior tilt & medial rotation of the scapula, whilst others recorded the opposite.  Indeed some were unable to find a significant difference in motion between the asymptomatic & pathological populations.

Ratcliffe et al concluded that their findings may have been due to the complex nature of the syndrome, if not reflective of a normal variation in the population.

The recent Scapular Summit, held last year in Kentucky, further reinforced this observation of inconsistent findings related to scapular orientation in SIS.  The consensus paper observed that scapular involvement may contribute significantly in the creation or exacerbation of shoulder dysfunction, whilst agreeing that the exact mechanisms are yet to be fully understood.

To this end, they concluded that "Scapular dyskinesis is probably most aptly viewed as a potential impairment to optimal shoulder function & should be evaluated & treated as part of the comprehensive treatment protocol".

In an attempt to identify risk factors for shoulder impingements using a prospective study design, Ann Cools' collaborations have enabled her to take normative data from 35 elite adolescent tennis players in Sweden.  Cools' has sought to identify variables in scapular position, muscle strength & flexibility between dominant & non-dominant shoulders, recording scapular upward rotation at various degrees of arm elevation, isometric scapular muscle strength & pectoralis minor muscle length.

In the study published in 2010, Cools et al reported significantly more scapular upward rotation, with significantly greater upper trapezius & serratus anterior strength on the dominant versus the non-dominant side.  In contrast, middle & lower trapezius strength data showed no significant difference between the two sides.  Pectoralis minor length was also shorter on the dominant side.

Whilst none of the subjects had symptoms or a history of symptoms of shoulder pain, these results will be very useful later on when reviewing the same population & tracking shoulder injuries throughout the subjects' tennis careers.  I'm looking forward to further papers being published using data from this population.

Specific range of movement patterns at the glenohumeral joint have been identified in throwers & sedentary individuals, with internal rotation deficits being commonly identified throughout the literature in conjunction with posterior capsular restriction.  External rotation ranges have been shown to either remain unchanged or slightly increased depending on the studies that you read.  

As I've illustrated then, SIS is a complex beast & there are a variety of potential factors that can contribute to its presentation.  I have discussed scapular dyskinesis, shoulder rotator muscle function & posterior capsule tightness but SLAP lesions, biceps pathology, rotator cuff pathology & shoulder instability may also have a role.

Subsequently, Dr Cools has proposed an assessment algorithm to guide the differential diagnosis of a shoulder examination.  The algorithm divides the battery of clinical tests into different components.  

Firstly, the impingement tests (Jobes, Hawkins & Neer tests) aim to differentiate between a posterosuperior glenoid impingement & a subacromial impingement as well as between pain & instability symptoms (Apprehension & Relocation tests).  The second batch of tests aims to define the involvement of rotate cuff pathology in the impingement symptoms (Full Can & Empty Can tests).  The scapular involvement in the impingement-related shoulder pain is evaluated using the Scapular Assistance Test (SAT) & the Scapular Retraction Test (SRT), whilst shoulder instability is assessed using provocative tests (Apprehension & Relocation tests) & laxity tests (Load & Shift tests).  Contributions to the equation by potential SLAP lesions & biceps pathology are established using the Speed's, O'Brien & Biceps Load II tests, whilst deficits in glenohumeral joint internal rotation are measured using a goniometer as well as a qualitative evaluation of the "end feel".

The results of the tests can help guide a user through the proposed algorithm & in conjunction with imaging investigations can provide a clinically reasoned differential diagnosis to many shoulder pathologies.

Whilst some clinicians have questioned the employment in the algorithm of some of the specific tests, what I like is the structure it lends to the assessment process.  A discussion of the meta-analysis conducted by Hegedus (2012) can help identify some of the tests that you may prefer to use to increase the validity & reliability of certain components of the algorithm but then that is what our own critical evaluation skills are designed for.

I hope the references might help guide you through a review of your shoulder evaluation processes & I would be really interested to hear of any other algorithms or protocols any of you use.

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