SHOULDER

Scapular Dyskinesis: Treatment With Elastic Therapeutic Taping

By Jennifer Illes, DC, Med. Ac., CKTI

Elastic therapeutic taping offers a unique combination of flexibility and support, providing practitioners with a tool to address a variety of conditions. Since 1973, when Kenzo Kase, DC, began developing the concepts in his practice, and then introduced its use in the 1980s, the range of applications has expanded tremendously.

Scapular dyskinesis, a factor in many shoulder complaints, is one of the many conditions that respond to this modality.

Shoulder pain is responsible for approximately 16 percent of all musculoskeletal complaints seen in the primary care setting,¹second only to low back pain in terms of patients seeking care for musculoskeletal ailments.² The problem some practitioners face is that traditional shoulder rehab fails 64-90 percent of the time because too much emphasis is placed on strengthening the rotator cuff (RTC) muscles using unidirectional isotonic strengthening³ – for example, conditioning the "mobilizers" of the shoulder (i.e., rotator cuff muscles) via bands and dumbbells.

What Is Scapular Dyskinesis?

Scapular dyskinesis describes an alteration in the normal static or dynamic position or motion of the scapula during coupled scapulohumeral movements. Other names for this condition include floating scapula and lateral scapular slide.⁴ As health care providers, we are concerned with scapular dyskinesis because alterations in scapular position and motion occur in 68-100 percent of patients with shoulder injuries.⁵

As the head of the humerus moves, the scapula simultaneously seeks a position of stability in relation to the humerus to maintain the humeral head in optimal alignment within the glenoid fossa. It is extremely important to note that scapular dyskinesis typically arises from a chronic shoulder condition (e.g., instability, labral tears, supraspinatous strain, impingement syndromes). As practitioners, therefore, we must first examine the shoulder to find the true pathology behind the scapular dyskinesis.

Scapulohumeral rhythm serves at least two purposes:

1. Preservation of the length-tension relationships of the glenohumeral muscles. When looking at a simple muscle physiology length-tension bell curve, one can note that both the hypertonic muscle (i.e., the one with too much overlap of actin and myosin filaments) and the hypotonic muscles (i.e., the ones with not enough overlap of the actin and myosin filaments) both produce a "weak" muscle. This is because both lack the proper length-tension ratio. With regard to the shoulder, the muscles do not shorten as much as they would without the scapula's upward rotation, so they can sustain their force production through a larger portion of the range of motion. Muscular imbalances can arise if the muscles lack a stable base of origin. Without muscular stability, muscles cannot develop maximal torque, resulting in decreased strength.


2. Prevention of impingement between the humerus and the acromion. Subacromial impingement can occur unless relative movement between the humerus and scapula is limited. Glenohumeral abduction is produced by force-coupling activity of both the RTC and deltoid, while the upward rotation of the scapula is produced by the serratus anterior and upper and lower trapezius muscles. We can implement elastic therapeutic taping techniques to facilitate these muscles to produce these motions, depending on what we find upon examination.

Common Causes of Scapular Dyskinesis

Postural abnormality: Many patients who present in our office have a visible upper-crossed syndrome. With increased cervical and thoracic spine flexion, there is a decreased upward rotation and decreased posterior tilt of the scapula.^6-7 These scapular abnormalities will cause decreased subacromial space and possibly an impingement-type syndrome of the shoulder.

Muscular contracture: This cause of scapular dyskinesis is particularly prevalent with patients suffering from upper-crossed syndrome. Tightness of the pectoralis minor or short head of the biceps can anteriorly tilt the scapula, due to their attachments to the coracoid process. Moreover, shortening of pectoralis major can restrict posterior clavicular motion (the clavicle should rotate posteriorly approximately 55° after 90° of shoulder abduction), thereby affecting normal scapular movement.

Muscle weakness (faulty movement patterns): Scapular muscle fatigue may lead to altered glenohumeral proprioception, muscular inhibition, and impaired coordination of scapular movements and timing. The most commonly inhibited hypotonic muscles are the serratus anterior, lower and middle trapezii, and rhomboid muscles. Inhibition is seen as a decreased ability for muscles to stabilize the scapula, and also as an unsystematic order of normal muscle-firing patterns. Most commonly, we tend to see this trend first with the serratus anterior and lower trapezius.

A Treatment Method Using Elastic Therapeutic Tape

There are several different ways to implement elastic therapeutic taping techniques. Each case is unique in that there are different shoulder and/or postural conditions that may cause scapular dyskinesis, and we may be dealing with these conditions in different phases of healing.

In the case modeled below (see images), I decided to tape for a fictitious impingement syndrome due to a subacromial bursitis causing a notable scapular dyskinesis. In the first image, inhibition was created on the upper trapezius by going from insertion to origin on the muscle belly. In addition, there is a facilitation piece of tape on the serratus anterior muscle from origin to insertion. Both of these pieces of tape were put on with the model with pre-stretched tissue tension. It is very important to facilitate the serratus anterior and/or lower trapezius musculature in this particular case.

The third piece of tape that was applied was a mechanical correction to try to proprioceptively reposition the scapula into posterior tilt. This piece of tape was anchored inferior to the coracoid process (second image) and then stretched with approximately 75 percent of tape tension while the patient had his arm into external rotation and abduction with slight extension. All three pieces of tape help to decrease the anterior tilt of the scapula, which would theoretically increase the space under the subacromial space.

Takeaway Points

Scapular dyskinesis can have many different etiologies; however, it is a secondary concern to another pathology or condition. It is for this reason that proper diagnosis must be made once a scapular dyskinesis is noted. In the case illustrated in the images above, elastic therapeutic taping can help the patient with facilitation and/or inhibition of muscles to help normalize muscular tone. By normalizing muscular tone, normal firing patterns – and therefore proper scapulohumeral mechanics – can possibly be restored. Taping can also be used to help create a mechanical correction of the scapula itself through proprioceptive receptors in the skin.

References

1. Van der Windt DA, Koes BW, de Jong BA, Bouter LM. Shoulder disorders in general practice: incidence, patient characteristics, and management. Ann Rheum Dis, 1995;54(12):959-964.
2. Steinfeld R, Valente RM, Stuart MJ. A common sense approach to shoulder problems. Mayo Clin Proc, 1999;74(8):785-794.
3. Kibler WB, McMullen J. Scapular dyskinesis and its relation to shoulder pain. J Am Acad Orthop Surg,2003;11:142-151.
4. Kibler WB. The role of the scapula in athletic shoulder function. Am J Sports Med, 1998;26(2):325-337.
5. Kibler WB, McMullen J. Scapular dyskinesis and its relation to shoulder pain. J Am Acad Orthop Surg,2003;11:142-151.
6. Ludewig PM, Cook TM, Nawoczenski DA. Three-dimensional scapular orientation and muscle activity at selected positions of humeral elevation. J Orthop Sports Phys Ther, 1996;24(2):57-65.
7. Finley MA, Lee RY. Effect of sitting posture on 3-dimensional scapular kinematics measured by skin-mounted electromagnetic tracking sensors. Arch Phys Med Rehabil, 2003 Apr;84(4):563-8.