Scapular Dyskinesis & The Overhead Athlete

 "The reason why we don't lift overhead, is because we stopped lifting overhead" - Arthur Dreschler 

Due to our forward and front facing world, our anatomical position has gone down the poop shoot, especially our head and shoulder position. Today I am going to talk about the shoulder, specifically the scapula and its importance for our overall athletic form and function. The scapula plays a CRUCIAL role in allowing our shoulder to move in an impressive range of motion. It has been difficult to track scapular motion because of the relatively deep position of the scapula, the overlying muscles, the potentially complex nature of the position and motion of the scapula during arm motions and functional tasks. Sometimes altered scapular motion is noticeable and occurs more than people think. 

Posterior View

What is Scapular Dyskinesis? 

With overhead athletes (Tennis, Baseball, Softball, Track & Field Throwers, and Swimmers) we see shoulder issues more and more everyday. It has been suggested that 68-100% of all shoulder injuries Scapular Dyskinesis has been present, which means an abnormal movement of the scapula i.e. 'dys' - alteration of, 'kinesis' - movement. It can cause several of the following:

• Muscle Imbalances
• Rotator Cuff Weakness
• Nerve Injury
• Muscle Injury
• Ligament Damage
• Proprioceptive Dysfunction

We often can notice Scapular Dyskinesis in the following conditions:

• Impingement - Reduced upward rotation and winging of the acromion
• Loss of maximal rotator cuff muscle activation capability
• Labral Injury - altered scapular positioning and motion increases stress on the anterior shoulder, and can increase the ‘peel-back’ load on the labrum
• More traumatic injuries such as clavicle fractures and AC joint injuries

3 Types of Diagnosis

In the clinical situation 3 types of scapula dyskinesis can be identified, although there is some overlap between the 3 types.

Originally posted on Shoulderdoc

Type 1 - Infero-medial scapula border prominence

This becomes more evident in the cocking position of overhead sports.  It is often associated with tightness at the anterior side of the shoulder (in flexibility of the pectoralis major/ minor muscles) and weakness of the lower trapezius and serratus anterior muscles.  posterior tipping of the scapula is responsible for functional narrowing of the subacromial space during the overhead motion, leading to pain in the abduction/externally rotated position.  This is often noticed in the early stages of shoulder disorders.

Type 2 - Medial border prominence

This pattern is winging of the entire medial border of the scapula at rest.  It becomes more prominent in the cocking position and after repetitive elevation of the upper extremity.  It is caused by fatigue of the scapula stabilising muscles (trapezius and rhomboids).

Type 3 - Supero-medial border prominence

This type of dyskinesis is displayed as a prominence of the superior medial border of the scapula and often associated with impingement and rotator cuff injury.

Word Key

Medial - Toward the center of the body; inwards

Anterior - Front

Posterior - Back

Abduction - Moving a body part away from the central axis of the body

Superior - At the top; towards the head



 Below is two videos of a patient with Scapular Dyskinesis. Notice the difference in both videos 

Video 1- Patient has pretty bad winging of the right scapula with poor control. Winging can cause injury or dysfunction of the muscles and nerves that supply the muscles. 

 


Video 2 - Same patient after 10 minutes of scapular retraining, much better.

Why This Problem Exists

The Serratus Anterior primary job is to upwardly face the glenoid socket during overhead movement, which allows the rotator cuff to maintain an advantageous position in controlling the humeral head.

In short, if your Serratus and scapular stabilizers are not functioning properly these characteristics can become prevalent. We want to improve the stability of the shoulder and help prevent Shoulder Dyskinesis.

 One of many exercises that aids in proper scapular and muscle involvement

Treatment

Cools, Struyf, Mey, Maenhout, Castelein, Cagnie (2013) published:

The below picture summarizes a recently published clinical reasoning algorithm that the clinician may use in the treatment of scapular dyskinesis. In the upper part of the algorithm, a summary is presented of the possible causes for scapular dyskinesis, as described in the first part of this review, whereas in the lower part therapeutic strategies are suggested. The algorithm is further divided into two columns, as a patient presenting with scapular dyskinesis may have flexibility problems or muscle performance problems, or both. Each side of the algorithm needs a specific approach regarding rehabilitation. Flexibility deficits need to be addressed by stretching and mobilisation techniques, whereas muscle recruitment normalisation is the main goal for the patient who has muscle performance problems. If both flexibility deficits and muscle dysfunction are responsible for the scapular dyskinesis, both problems should be addressed. It is imperative to determine whether the flexibility deficits are primary or secondary, based on the relative weakness of the antagonist. In the first case, reducing flexibility problems should precede motor control learning; in the second case, gaining stability may relax the tight muscle.

References

Ball (2011, May 17). The Shoulder Position & Why Your Traps Aren't Actually Huge. Retrieved from http://www.reallifehealth.ca/exercise/the-shoulder-position-and-why-your-traps-aren’t-actually-that-huge

Sports PhysioTherapist (2011, October 28). Assessment of Scapular Dyskinesis. Retrieved from http://www.thesportsphysiotherapist.com/assessment-of-scapular-dyskinesis/

Cools, Struyf, Mey, Maenhout, Castelein, Cagnie (2013, May 18). Rehabilitation of scapular dyskinesis: from the office worker to the elite overhead athlete. Retrieved from http://www.physiotherapy.asn.au/DocumentsFolder/CONFERENCE%202013/Sports%20-%20Pre%20Conference%20Reading%20Material.pdf