It is important for anyone working with clients to recognise uncontrolled or faulty movement .  It is only a matter of time before he’s off to his health professional with a strain or pain. By Jacqui Clark

When a swimmer has inadequate backward tilt of the scapula in full elevation of the arm, he is at risk of an impingement injury. When a person lifts weights in the gym doing lateral raise (see fig. 1) with herlevator scapulae muscles and rhomboids pulling harder than her serratus anterior and trapezius muscles, she forces her scapula into downward rotation, instead of upward rotation, again risking an impingement injury.

 
Figure 1. Dumbbell lateral raise

Rotator cuff tendons can be slowly irritated and worn if the scapula is not controlled adequately and can become an accident waiting to happen when an unexpected heavy lift or a fall sends the irritated tissue past its threshold of tolerance. Often when a person reports an injury it can be a seemingly small incident that caused the damage. This is when the treating physiotherapist would suspect a previous movement pattern that was uncontrolled, leading to tissue vulnerability.

A “clunky,” “clicky” or “grating” shoulder joint can be the result of inadequate control from the rotator cuff muscles, failing to control the head of the humerus in the glenoid.  Uncontrolled joint gliding (joint translation) can cause over-stretch or over-compression of soft tissue structures around the joint.  These can also lead to a painful shoulder.

It is important for anyone working with clients to recognise uncontrolled or faulty movement patterns and correct them before they result in injury.

There is a big difference between strengthening the rotator cuff and retraining low threshold motor control in the cuff muscles. Strengthening all the shoulder muscles together such as the deep and superficial medial rotators, does not necessarily improve the motor control problems. These would be the delayed timing in rotator cuff particularly the subscapularis and long head of biceps in this example; and their threshold of activation which should be lower than the superficial muscles such as pectoralis major and latissimus dorsi. Retraining motor control in an active person involves specific facilitation and deep muscle activation before integrating into strength training and normal function.

The scapula muscles that become less efficient are the serratus anterior and the trapezius muscles. These are the muscles that upwardly rotate the scapula to avoid impingement under the acromion or coraco-acromial arch.  See Figure 2. Strengthening the scapula muscles without regard for the specific function of the individual muscles is unlikely to have the desired effect of changing the scapula control under load and in normal function. Strengthening or continuing sport with poor movement pattern control puts the person at risk of injury.

Figure 2. Scapular upward rotation

After injury, pain inhibits low threshold stability muscles.  It can become more difficult to regain motor control due to changes that take place in the central nervous system after injury.  Accurate assessment of the patient by the qualified health professional is necessary to sub-classify their problem, not just the tissues that are damaged, but the pain mechanism they present with, their motor function, their proprioceptive and sensorimotor coordination and any psychological or psychosocial (these are different) factors.  Then clinical prediction rules must be used to direct rehab according to their particular diagnostic features.

Assessment and motor control techniques, with their integration into functional training will be covered in Jacqui Clark’s Shoulder Girdle Movement Analysis and Motor Control Training Workshop.