Scapular Control

The role of scapular control impairment in shoulder impingement and neck dysfunction has been widely discussed over the last decade.  A recent position statement was published in the Journal of Orthopaedic and Sports Physical Therapy  (November 2009) outlining the current state of the art.  There were three broad areas of discussion including the following:

1. What do we know?
2. What are the important gaps in our knowledge?
3. Where do we go from here?

It was acknowledged that many tests have been identified which can be performed reliably to evaluate scapula position, but few have been shown to be clinically meaningful in terms of demonstrating correlation with biomechanical dysfunction, pathology, symptoms or outcomes.

Testing Scapular Dysfunction

It was concluded that the following tests be used to assess scapular dysfunction.

1. Clinical observation of scapular dyskinesis.

2. Clinical tests that alter symptoms.

3. Manual muscle testing of the periscapular muscles.

4. Evaluation of neck, thorax and shoulder postural alignment as potential associated contributory factors.

5. Observation of scapular dyskinesis – defined as positive when subjects show less upward rotation, less clavicle elevation and less clavicle retraction during the movements of arm flexion and abduction.  This is also substantiated by the observation of scapular winging during the same motions or prominence of any portion of the medial scapula border.

Symptom Alteration Tests

These tests are designed to detect relevant scapular dysfunction in patients with shoulder pathology by determining if shoulder symptoms are changed after manually altering scapular position and motion.

1. Scapular reposition test:

Here the scapula is moved toward posterior tilt and external rotation while the patient elevates the arm.  Observation for influence on pain and range of motion is noted.

2. Scapular retraction test:

Scapula is passively moved towards posterior tilt and external rotation with slight voluntary retraction.  This is similar to the reposition test except it involves an active muscle contraction component.

3. Scapular assistance tests:

Here scapula upward rotation is manually assisted during the arm elevation movement.  It appears that by altering scapular kinematics and increasing posterior tilt and decreasing scapular elevation this facilitates opening of the subacromial space.

Manual Muscle Testing

Specific positional testing of the muscles around the scapula using manual tests and/or strength measurement gauges is the recommended protocol.  Isokinetic testing when available has been shown to identify peak torque deficits in athletes with overhead impingement symptoms.

Posture

While this is commonly held to be a contributory factor, there are no accepted or validated clinical measures to confirm this.  The spectrum of subcomponents of postural deviation involving thoracic stiffness, head position, myofascial tightness, muscle imbalance, glenohumeral positioning and trunk alignment are all biomechanical features which can influence scapula / arm position but have not been shown to be closely correlated in existing research.

What are the gaps in our knowledge?

The ability to distinguish between surgical and non-surgical cases with clinical examination remains unclear.

The correlation between scapula position tests and symptoms is unclear.

There are no quantitative measurement techniques that allow characterisation of scapular dyskinesis.

Clinical inclinometer methods can give good information regarding three-dimensional position.

Where do we go from here?

There is a need for an easily implementable clinical tests and measures to quantify scapular dysfunction.

There is a need to determine the meaningfulness of scapular dysfunction.

There is a need to determine the relationship between scapular dysfunction and symptoms disability and outcome in patients undergoing rehabilitation.

In conclusion it was agreed that scapular dyskinesis is frequently associated with shoulder symptoms.  However, it is unclear at this point exactly what role dyskinesis plays, what types of examinations would best demonstrate its presence and its contribution to dysfunction.  It was agreed that clinical observation of scapular dysfunction and clinical tests that alter symptoms should form the basis for scapular evaluation.  Other tests of strength and flexibility should compliment the basic exam.

Clearly we still have some way to go.

Enjoy the clinical challenge.

David