Open access peer-reviewed chapter

Scapular Dyskinesis

Written By

Mohammed Hegazy

Submitted: 06 April 2022 Reviewed: 07 April 2022 Published: 09 July 2022

DOI: 10.5772/intechopen.104852

From the Edited Volume

Shoulder Surgery for RC Pathology, Arthropathy and Tumors

Edited by Dimitrios D. Nikolopoulos and George K. Safos

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In order for correct shoulder function to occur, the scapula plays a number of responsibilities. These functions include synchronous scapular rotation during humeral motion, providing a stable basis for rotator cuff activation, and acting as a kinetic chain link. Scapular dyskinesis is defined as a change in the resting or dynamic position of the scapula. Scapular dyskinesis is a nonspecific response to a painful shoulder ailment rather than a specific response to glenohumeral pathology. Visual assessment of the scapular position at rest and during dynamic humeral motions, as well as objective posture measurements and scapular corrective techniques, is used to diagnose scapular dyskinesis. Treatment for scapular dyskinesis focuses on improving dynamic scapular stability by improving the motor control and strength of scapular stabilizers, as well as the flexibility of tight muscles and other connective tissues.


  • kinetic chain
  • dynamic stability
  • scapular dyskinesis

1. Introduction

Scapular dyskinesis is a disorder characterized by altered scapular mechanics and motion, with “dys” denoting alteration and “kinesis” denoting motion [1]. Scapular dyskinesis is not always a medical word. In fact, it has been seen in both asymptomatic and symptomatic patients with shoulder girdle discomfort [2, 3, 4, 5]. It was thought to be caused by abnormalities in scapular stabilizing muscle activation [6], injury to the long thoracic, dorsal scapular, or spinal accessory nerves, or potentially decreased pectoralis minor muscle length [7].

SICK (scapular malposition, inferior medial border prominence, coracoid pain and malposition, and dyskynesis of scapular motion) was coined by Burkhart et al. [8], who recognized the importance of scapular dyskinesis in overhead athletes complaining of shoulder pain. As a result, this term should only be used when scapular dyskinesis is clearly present.


2. Clinical features of scapular dyskinesis

The anterior and/or posterosuperior aspects of the shoulder, as well as the upper region of the lateral arm below the acromion, may be painful in the symptomatic patient with scapular dyskinesis. Pain may radiate into the lateral part of the neck along the UT or follow a radicular pattern along the upper extremity. Pain in the coracoid region due to constriction of the pectoralis minor as a result of downward tilt and lateral displacement of the coracoid is the most common presenting symptom, followed by posterosuperior scapular pain [8].

Three dyskinetic patterns were found by Kibler et al. [9]: The inferomedial border of the scapula is prominent due to an excessive posterior tilt along a horizontal axis in the plane of the scapula; when this type is isolated, the scapula may be lower than the opposite side (Figure 1). Due to excessive external rotation around a vertical axis via the plane of the scapula, Type II is characterized by the prominence of its entire medial border (Figure 2). These types are frequently linked to superior labrum injuries. Type III is characterized by upward rotation of the scapula’s superomedial border around a horizontal axis perpendicular to the plane of the scapula, resulting in abnormal superior migration of the scapula (Figure 3); this pattern is linked to a reduction in the acromiohumeral space and the possibility of rotator cuff injuries. The pattern of Type IV is symmetric.

Figure 1.

Type I dyskinesis (adopted from [10]).

Figure 2.

Type II dyskinesis (adopted from [10]).

Figure 3.

Type III dyskinesis (adopted from [10]).


3. Role of scapula

The scapula has three key functions in producing smooth, coordinated movement throughout the shoulder girdle. To sustain the glenohumeral connection and provide a stable foundation for muscle function, these tasks are intertwined. The scapula’s primary function is to maintain dynamic stability and regulated motion at the glenohumeral joint. The scapula must move in sync with the moving humerus in order to keep the humeral head restricted within the glenoid during the whole range of shoulder motion [11].

Maintaining appropriate glenoid fossa alignment not only provides for ideal bony restraint, but it also aids muscular constraint by maintaining proper length tension relationships for efficient rotator cuff muscle contraction, squeezing the humeral head into the fossa [11, 12]. The scapular musculature must maintain dynamic stability while also providing regulated movement. The scapula must be protracted in a smooth fashion laterally and then anteriorly around the thoracic wall during throwing motions to allow the scapula to retain a normal positional relationship with the humerus. This motion is controlled by eccentric contraction of the medial-stabilizing musculature (mostly the rhomboids and middle trapezius), which allows part of the deceleration forces experienced during the follow-through phase to be dissipated [11].

With overhead exercises, the scapula must also rotate upward to free the acromion from the rotator cuff [13]. The scapula travels laterally in normal abduction for the first 30°–50° of abduction. As the shoulder reaches maximal elevation, the scapula rotates around a fixed axis across an arc of roughly 65° [14]. With overhead activity, the 2:1 ratio between glenohumeral abduction and scapulothoracic rotation is explained by this motion. To tilt the acromion upward and reduce the possibility of impingement and coracohumeral arch compression, upward rotation and elevation are necessary (Figure 4) [16].

Figure 4.

Scapulohumeral rhythm (adopted from [15]).

The scapula’s second function is to serve as a basis for muscular attachment. The muscles that control the position of the scapula attach to the medial border of the scapula, stabilizing it. Scapular motion is primarily controlled by this musculature through synergistic cocontractions and force couples, which are paired muscles that regulate the movement or position of a joint or a body part [17, 18, 19, 20]. Muscles that attach along the lateral edge of the scapula perform gross motor tasks of the glenohumeral joint in addition to acting as scapular stabilizers. The rotator cuff muscles adhere to the whole surface of the scapula and are positioned so that their most efficient stabilizing activity occurs when the arm is abducted between 70° and 100° [21]. The humeral head is compressed into the socket by these muscles, which are referred to as a “compressor cuff” [20].

The scapula’s third function is best described as the link in the proximal-to-distal energy transfer that enables for the ideal shoulder placement for optimal performance [16, 22, 23, 24]. The scapula plays a critical role in transporting enormous forces and high energy from the principal sources of force and energy, the legs and trunk, to the actual delivery mechanism of the energy and force, the arms and hands [23, 24, 25]. Forces generated in the proximal segments must be efficiently and effectively transferred via the shoulder and into the hand. The scapula provides a secure and regulated platform for these activities, allowing the entire arm to rotate as a unit around the sturdy base given by the scapulothoracic joint and the glenohumeral joints [20].


4. Scapular kinetics during arm elevation

The musculature connected to the scapula, humerus, thoracic cage, and spinal column controls the scapulothoracic articulation. During the first phase of glenohumeral elevation, the UT and lower SA operate as a force couple to cause scapular upward rotation. The LT contributes more in the intermediate phase of glenohumeral elevation, while the LT, UT, and lower SA are roughly equally active in the final phase of glenohumeral elevation. The scapular muscle is responsible for stabilizing the scapula and supporting the glenohumeral joint’s base. A loss in the surrounding musculature’s ability to stabilize the scapula may result in a shift in scapular position or motion. The length-tension relationship can be adjusted by changing the scapular position.

A malfunctioning rotator cuff can theoretically be caused by changes in scapular posture and scapular muscular strength [26]. The force couples’ primary roles are to provide maximum congruency between the glenoid fossa and the humeral head in order to provide dynamic glenohumeral stability and maintain an ideal length-tension relationship [12, 25]. The UT and LT muscles, along with the rhomboid muscles and the SA muscle, are the appropriate force partners for scapular stabilization. The LT and SA muscles, in combination with the UT and rhomboid muscles, are the suitable force partners for acromial elevation (Figure 5) [20, 28].

Figure 5.

Force couples of scapular stabilization (adopted from [27]).


5. Scapular kinematics during arm elevation

Normal shoulder function depends on scapular location on the thorax and control during motion. The scapula should upwardly rotate and posteriorly tilt on the thorax when raising the arm overhead (Figure 6 and Table 1) [30]. The most common scapulothoracic motion is upward rotation. The scapula’s motion in response to changes in scapular internal rotation angle is more variable between participants, investigations, elevation planes, and elevation range of motion points [30, 31]. Early in the range of arm elevation in scapular plane abduction and flexion, slight increases in scapular internal rotation may be normal. Although there is minimal data, it is generally acknowledged that end range elevation in healthy patients requires some scapulothoracic external rotation [30].

Figure 6.

Scapular motions from (a) posterior (upward/downward rotation), (b) superior (internal/external rotation), and (c) lateral (anterior/posterior tilting) views. Axes of rotation are indicated as black dots (adopted from [29]).

MotionHealthyImpingement or rotator cuff disease
Primary scapular motionUpward rotationLesser upward rotation
Secondary scapular motionPosterior tiltingLesser posterior tilting
Accessory scapular motionVariable internal/external rotationGreater internal rotation
Presumed implicationsMaximize shoulder range of motion and available subacromial spacePresumed contributory to sub acromial or internal impingement

Table 1.

Summary of scapular kinematics during arm elevation in healthy and pathologic state [29].

The sternoclavicular (SC) and acromioclavicular (AC) joints move together in scapulothoracic kinematics. In healthy people, substantial 3-D motions occur at both the SC and AC joints during arm elevation [30, 32, 33]. As arm elevation progresses upward, the clavicle exhibits a pattern of mild elevation and progressive retraction [30, 32]. At the AC joint, the scapula rotates upwardly, internally, and posteriorly relative to the clavicle at the same time [33]. Elevation/depression and abduction/adduction scapulothoracic “translations” have also been described in the past [33, 34]. These movements are caused by clavicular motions at the SC joint. SC elevation causes scapulothoracic elevation, and SC protraction/retraction causes abduction/adduction [33].


6. Potential biomechanical mechanisms contributing to alterations in scapular kinematics

Pain, soft tissue tightness, muscle activation or strength imbalances, muscle exhaustion, and thoracic malposture are all potential contributors to aberrant scapular kinematics (Table 2) [26].

Potential biomechanical mechanismsAssociated effects
Inadequate muscle activationLesser scapular upward rotation and posterior tilt
Excess UT activationGreater clavicular elevation
Pectoralis minor tightnessGreater scapular internal rotation and anterior tilt
Posterior soft tissue tightnessGreater scapular anterior tilt
Thoracic mal postureGreater scapular internal rotation, anterior tilt and lesser scapular upward rotation

Table 2.

Potential biomechanical mechanisms contributing to scapular kinematic alterations [29].

6.1 Effect of muscle activity alteration on scapular kinematics

Muscle activation is the most commonly studied feature in patient populations; however, these changes in muscle activity are rarely connected to scapular kinematic changes. Significantly less SA muscle activation and greater UT activation were found in subjects with impingement or shoulder dysfunction who had less scapular upward rotation and posterior tilt as well as greater scapular elevation [35, 36].

When these findings are combined with knowledge of these muscles’ ability to induce or govern scapular rotations, the lesser serratus activations may play a key role in the observed lower posterior tilt and upward rotation. Increased UT activation is likely related to greater scapula elevation by increasing clavicular elevation [37]. Scapulothoracic muscle activation timing has also been studied. In competitive freestyle swimmers with shoulder impingement, the temporal recruitment pattern of the UT, LT, and SA showed much more variability than in a control group of competitive swimmers [38].

In comparison to a control group, overhead athletes with shoulder impingement showed significantly delayed activation of the middle trapezius (MT) and long trapezius (LT) in response to an unexpected drop of the arm from an abducted posture [39]. The experimental production of muscular fatigue is a model for relating muscle activation patterns to changes in scapular kinematics. However, none of the studies on shoulder fatigue that have been found so far have tried to tire isolated scapulothoracic muscles, and the inability to fatigue a particular muscle or muscle group hampers interpretation of the results. One study found that after a resisted humeral external rotation fatigue treatment, scapular upward rotation, posterior tilt, and external rotation all decreased significantly. However, another study that used resisted humeral external rotation to induce shoulder fatigue reported significant increases in scapular upward rotation rather than decreases. The findings for reduced posterior tilt after fatigue were identical in direction in both studies [40, 41].

6.2 Effect of pain on scapular kinematics

The impact of pain on muscle activation patterns is likewise a mystery. Interestingly, during repetitive bilateral flexion in otherwise healthy subjects, experimentally induced pain caused by injection of hypertonic saline directly into the upper, middle, and lower divisions of the trapezius resulted in decreased UT and increased LT activation on the painful side and increased trapezius activation on the contralateral side [42].

6.3 Effect of soft tissue tightness on scapular kinematics

Another possible cause for the development of the scapulothoracic changes found in patients is soft tissue stiffness of muscles or tissues that can inhibit normal scapular motions during arm raising. Pectoralis minor and posterior shoulder stiffness have both been studied [7, 43].

6.3.1 Effect of pectoralis minor tightness on scapular kinematics

The pectoralis minor can provide scapular internal rotation, downward rotation, and anterior tilt thanks to its attachments from the coracoid process to the third to fifth ribs. Excessive active or passive tension in this muscle may prevent normal scapular upward rotation, posterior tilt, and maybe scapular external rotation from occurring during arm raising. Those with a short pectoralis minor resting length, indicative of muscular tightness, had considerably less scapular posterior tilt and more scapular internal rotation during arm elevation than those with a long pectoralis minor resting length [7].

A rounded shoulder and forward head position is a frequent postural presentation in both sedentary people and overhead sportsmen. The subacromial space shrank as the shoulder progressed from a retracted to a protracted posture, according to dynamic magnetic resonance imaging [44]. Previously, this scapula posture was linked to diminished pectoralis minor flexibility or adaptive shortening. This decreased flexibility might impact scapula posture as well as create axillary artery compression, resulting in neurovascular complaints. Because of the prolonged elongation, this postural presentation might lead to stretch weakness of the posterior scapular musculature, especially the rhomboid muscles and lower trapezius [45, 46].

6.3.2 Effect of tightness of posterior capsule on scapular kinematics

Tightness in the glenohumeral joint’s posterior capsule, or posterior shoulder, has also been proposed as a mechanism for changing scapular kinematics by passively “pushing” the scapula laterally over the thorax, especially during humeral internal rotation in raised arm positions [20]. Subjects with no shoulder complaints but a glenohumeral internal rotation range-of-motion deficit on their dominant arm (indicative of posterior shoulder tightness) were compared with a control group with no such deficit in a subsequent study. The humerus was elevated 90° into both flexion and abduction postures, and scapular positioning was evaluated at end range humeral internal rotation. At end range humeral internal rotation locations, the group with less glenohumeral joint internal rotation range of motion had considerably more scapular anterior tilt [7, 43].

6.4 Effect of thoracic mal posture on scapular kinematics

Changes in scapular location have also been linked to thoracic posture. When healthy volunteers were requested to sit in a “slouched” position and raise their arm, scapular upward rotation and posterior tilt were dramatically reduced, whereas scapular internal rotation and scapular elevation were significantly increased [47]. With the arm relaxed at the side, increased scapular anterior tilt and scapular internal rotation have also been reported in women with increasing thoracic kyphosis, as well as increased scapular anterior tilt with age [48].


7. Assessment of scapular dyskinesis

The reliable and correct identification of the presence or absence of scapular position or motion abnormalities is one of the problems of the clinical diagnostic procedure in people who have shoulder pain. In one study, moderate kappa values for inter-tester and intra-tester reliability were obtained employing blinded evaluators who assessed recorded patients [9]. Another study found lower inter-rater reliability when patients were recorded and examined by therapists who were unaware of the individuals’ symptom status. These dependability levels are below what is ideal for routine clinical use. Improved reliability could be achieved through direct evaluation (as opposed to film), improved training, or revision of movement category definitions [49].

The examination begins with the patient’s arm at a rest. Only one, two, or all three dyskinesis patterns can be found. The stability of the SC and AC joints should be tested in the resting position, and the clavicle should be inspected for any shortening, angulation, malrotation, or hypermobility. The coracoid should be palpated to establish its position in relation to the opposite side, as well as any soreness along its medial border, where the pectoralis minor is implanted. After that, the subject is asked to raise and then drop his or her arm in the sagittal and/or scapular planes. The third stage involves watching the scapular action while lifting and lowering the arm with a 3–5 pound weight [50].

A study was conducted in asymptomatic persons and patients with shoulder discomfort to examine the reliability of the clinical assessment [2]. The patients’ medial and superior scapular borders were measured as they conducted three to five arm elevation trials in the sagittal and scapular planes. The scapular motion was classified by two assessors using either the Kibler et al. [7] approach or a two-type method (yes/no). Yes, if one or more dyskinetic patterns are present, and no, if normal motion is present. To identify the presence of dyskinesis and to establish criteria validity of the two approaches, a 3-D kinematic analysis utilizing an electromagnetic tracking device was also done.

The yes/no method had a greater inter-rater agreement (79%) than the method used by Kibler et al. [51] (61%). The former strategy demonstrated a higher sensitivity (76%) and positive predictive value (100%) than the latter (74%). Multiple-plane asymmetries were detected in a substantially higher percentage of symptomatic participants (54%) than in asymptomatic subjects (14%). The researchers concluded that the yes/no technique is a good screening tool for scapular dyskinesis [10].

In contrast to these findings, Ellenbecker et al. [52] discovered that the Kibler et al. [7] technique of evaluation had a low reliability in baseball players who were videotaped performing five repetitions of scapular plane elevation while gripping a 2-pound weight. McClure et al. [50], Tate et al. [53] described a new approach for identifying scapular dyskinesis and determining its severity than Kibler et al. [7], which they called the scapular dyskinesis test. Overhead athletes were asked to do five repetitions of bilateral weighted shoulder flexion and abduction.

Dysrhythmia (premature or excessive scapular elevation or protraction, nonsmooth or stuttering motion on elevation or lowering, or fast downward rotation during lowering) and/or winging are symptoms of scapular dyskinesis (medial border or inferior scapular angle posteriorly displaced from the thorax). Normal motion, slight abnormalities, or evident abnormalities were assigned to each scapulothoracic deviation. The raters’ agreement in identifying normal or dyskinetic patients ranged from 75 to 80%. The presence of dyskinesis, on the other hand, was not linked to shoulder discomfort.

7.1 Clinical tests of scapular dyskinesis

Two corrective maneuvers can be used to confirm the kinematic changes and see if correcting them normalizes the arm motion and relieves the patient’s symptoms [5, 6, 54].

7.1.1 Scapular assistance test

During humeral elevation, the examiner passively supports the scapula into upward rotation and posterior tilt with the scapular assistance test (SAT) (Figure 7). While the patient elevates the arm, the test is performed by pushing upward and laterally on the inferior angle of the scapula and drawing the superior aspect of the scapula posteriorly. If symptoms are relieved and motion is increased, the test is positive. The SAT helps detect the scapular contribution to impingement and rotator cuff dysfunction by increasing acromiohumeral space [56].

Figure 7.

Scapular assistance test (adopted from [55]).

7.1.2 Scapular retraction/repositioning test

Tate et al. [57] described the scapular retraction/repositioning test (SRT). If a positive impingement test is found, the procedure can be redone with the scapula adjusted manually using the SRT (Figure 8). If symptoms are relieved and motion is increased, the test is positive. The SRT is performed by grasping the scapula with the fingers anteriorly contacting the acromioclavicular joint and the palm and thenar eminence posteriorly contacting the scapula’s spine, with the forearm obliquely angled toward the inferior angle of the scapula for additional support on the medial border. The examiner’s hand and forearm apply a mild push on the scapula in this manner to stimulate scapular retraction (scapular retraction test) or posterior tilting and external rotation (posterior tilting and external rotation test) (scapular repositioning test).

Figure 8.

Scapular retraction or repositioning test (adopted from [55]).


8. Rehabilitation of scapular dyskinesis

8.1 Stretching of pectoralis minor and posterior capsule

The pectoralis minor, posterior shoulder, and glenohumeral joint capsule are prospective candidates for stretching in individuals with scapular kinematic changes based on biomechanical variables [7, 43]. Stretching techniques for both of these tissues have been recommended. Despite the paucity of research, there have been comparisons made across procedures in terms of gains in range of motion or the potential to appropriately extend the targeted tissue [7, 58].

For posterior capsule tightness, McClure et al. [58] compared the effectiveness of a sleeper stretch, which is thought to better support the scapula, to a more standard cross-body stretch. After a 4-week stretching regimen, the passive internal rotation range of motion of asymptomatic participants was measured. Both stretching groups were also compared with a nonstretching control group. When compared with their nonstretched side, both stretching groups exhibited significant within-subject gains in range of motion. Surprisingly, only the cross-body stretch group improved much more than the control group.

In healthy subjects, the mean length change with three recommended stretches for the pectoralis minor was also compared. A unilateral self-stretch or corner stretch, as well as sitting and supine manual stretches, was among the stretches. Standing with the humerus abducted 90° and the elbow flexed 90°, the unilateral corner stretch requires placing the hand of the shoulder to stretch on the wall with the humerus abducted 90° and the elbow flexed 90°. The patient next twists their body away from the shoulder being stretched until they feel a slight strain in their pectoral muscles. The most length change was seen in the corner stretch, followed by the supine manual stretch. This shows that a corner stretch would be more successful in lengthening the pectoralis minor; however, the patients were not tracked over time in a randomized controlled trial [59].

8.2 Scapular muscle control and balance

The rehabilitation’s goal is to reestablish scapular muscle control and balance [60]. The goal is to equalize the ratio between the three sections of the trapezius, that is, UT/LT and UT/MT, and activate SA, because scapular dyskinesis suggests a larger activation of the UT and a lower control of the LT, MT, and SA [10]. The push-up plus, wall slide exercises, and shoulder elevation in the scapular plane have all been demonstrated to promote SA activation, with the push-up plus causing minimal UT activation [61, 62].

In the treatment of patients with shoulder discomfort and scapular motion abnormalities, strengthening or retraining the SA muscle warrants special consideration. The SA is the only scapulothoracic muscle capable of producing all of the desired 3-D scapular rotations of upward rotation, AC joint posterior tilting, and AC joint external rotation [37, 63]; hence, this recommendation is based on its biomechanical capabilities.

The serratus anterior’s position as an external rotator of the scapula may appear counterintuitive at first, given the serratus anterior’s lateral line of pull around the thorax, which has led to the serratus anterior being described as causing shoulder protraction. The clavicle protracts on the thorax at the SC joint, causing this protraction. Before this secondary joint rotation can take place, the SA’s line of action will pull the scapula’s vertebral border and inferior angle toward the chest wall, causing external rotation of the scapula at the AC joint and stabilizing the scapula on the thorax while the clavicle protrudes [63].

A number of activities to activate the SA muscle have been recommended based on electromyographic examinations, typically in healthy participants. Push-up plus and push-up progression exercises, the dynamic embrace, supine punch, and wall sliding workouts have all been used. Supine punch and push-up plus may be advantageous for people with SIS because they increase SA muscle activation while decreasing UT muscle activation. Patients with scapular control issues may benefit from starting with supine punch exercises that stabilize the scapula against the table [48, 57, 64, 65].

The LT is another muscle that can help to support the scapula and allow for upward rotation. Shoulder flexion in the side-lying position up to 135°, prone horizontal abduction with external rotation, and shoulder external rotation in side laying have been demonstrated to elicit a beneficial ratio of lowering UT activity and raising LT activity [66].

After a brief time of teaching, Mottram et al. [67] demonstrated that normal participants can learn and repeat movements to shift the scapula into posterior tilt and upward rotation without the assistance of a physiotherapist. They discovered that all regions of the trapezius were active using a motion analysis system and surface electromyography. In two of the four exercises described by Cools et al. [66], De Mey et al. [68] discovered that conscious patient control of the scapula orientation greatly improves the activation of the three components of the trapezius without affecting the UT/MT and UT/LT ratios.

Manual scapula adjustment has been demonstrated to improve supraspinatus strength and enhance subacromial space in individuals with subacromial impingement [5, 69]. Manual scapular assistance is utilized in clinical practice to provide tactile cueing for scapula positioning in order to identify patients for whom subacromial space is a contributing factor. Shirts intended to provide tactile stimulation for good scapular placement can also be used to provide postural cueing for scapular positioning. These shirts can be worn during a rehabilitation program as well as during everyday activities (ADLs) [70].

8.3 Correction of thoracic mal posture

Thoracic posture should also be addressed in the rehabilitation of patients with shoulder impingement or rotator cuff tendinopathy, given the evidence for changed scapular kinematics with thoracic kyphosis or flexed thoracic postures [29, 47]. This includes paying attention to maintaining erect postures while performing daily activities that require arm elevation, as well as when performing shoulder workouts. Where suitable to the patient’s presentation, exercises aimed at enhancing thoracic extension range of motion, strength, and endurance should be considered, keeping in mind that typical thoracic extension during arm elevation is only 10° or less [71].

Given the rhomboid’s capabilities as a downward rotator of the scapula, it was suggested that excessive reliance on shoulder retraction exercises for rhomboid training as part of a postural exercise program be avoided. Another therapy option to explore is joint mobilization in the thoracic spine. In a randomized clinical trial for shoulder impingement, adding manual treatment to a supervised exercise regimen resulted in much better results than supervised exercise alone [72]. In a sample of 14 patients with primary SIS, Conroy and Hayes [73] investigated the effect of joint mobilization as part of a comprehensive therapy plan. They found that mobilization reduced pain over the course of a day as well as pain during a subacromial compression test.

8.4 Therapeutic taping

The use of therapeutic taping in the treatment of shoulder discomfort has also been studied recently. Significant changes in posture and increases in arm elevation pain-free range of motion were observed with thoracic and scapular taping designed to change posture in both participants with shoulder impingement and healthy subjects. In the impingement group, there was no significant reduction in pain during arm elevation. However, for scapular plane abduction and flexion, the point in the range of motion when increased pain was first reported was much higher (average of 15° and 16° increase in pain-free range of motion, respectively). Another study found that using taping reduced upper trapezius electromyographic activation while increasing lower trapezius electromyographic activation in participants with shoulder impingement during arm motion [74, 75].

8.5 Rhythmic stabilization exercises

Wilk and Arrigo [76] devised specific exercises to regulate the scapulothoracic joint’s muscle force coupling while also stimulating proprioceptive and kinesthetic awareness to improve the scapulothoracic joint’s neuromuscular control. Because of a prevalent weakness, the scapular retractors, protractors, and depressors are commonly emphasized with isolation strengthening exercises. The exercise routine for the scapula can include neuromuscular control and PNF drills. Proprioceptive awareness can be harmed as a result of macro or microtrauma; consequently, early in the rehabilitation program, the clinician should undertake drills to restore the neurosensory qualities of the joint capsule to heighten the sensory awareness of the afferent mechanoreceptors [77, 78].

8.5.1 Types of rhythmic stabilization exercises Open kinetic chain rhythmic stabilization exercises

Manual rhythmic stabilization exercises are performed with the arm in the scapular plane at 30° of shoulder abduction, starting with the internal and external rotators. A cocontraction of the internal and external rotators is enabled by varying manual input, which necessitates the patient’s isometric stability. These stability drills can also be done with the arm at around 100° of elevation and 10° of horizontal abduction. Because of the combined centralized resultant force vectors of both the rotator cuff and deltoid musculature that induce humeral head compression, this “balanced position” is a favorable beginning point [14, 79]. Closed kinetic chain rhythmic stabilization exercises

Proprioceptive drills are used to advance closed kinetic chain workouts. Advanced weight-shifting drills include a table push-up on a ball or on an unstable surface. Completing a push-up exercise on an unstable or modified surface has been demonstrated to create higher upper trapezius, middle trapezius, and serratus anterior activation in overhead throwing athletes with impingement than performing a regular push-up exercise. While the patient’s hand is on a little ball and the physician performs perturbation drills on the patient’s arm, wall stabilizations are conducted [15].


9. Conclusions

Scapular dyskinesis is a multifactorial disorder characterized by changes in scapular kinematics during position and motion. Scapular dyskinesis should be assessed on both static and dynamic levels, with treatment focusing on scapula motor control and increasing the force couple around the scapula to improve shoulder dynamic stability.



I thank ALLAH for all things in my life. My thanks to my parents, my wife, and my dear sons.

Notes/thanks/other declarations

Thanks to ALLAH for helping me to finish this work.

Acronyms and abbreviations


upper trapezius


middle trapezius


lower trapezius


serratus anterior


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Written By

Mohammed Hegazy

Submitted: 06 April 2022 Reviewed: 07 April 2022 Published: 09 July 2022