Blog by: Kaushik Talukdar
Edited by: Suryakant Tripathi
People spending considerable amount of time in overhead activities such as occupational overhead lifting, overhead exercises in the gym or involved in throwing and racket sports such as cricket and tennis often tend to complain of shoulder pain at some stage of their life. Overhead activities require flexion, abduction and external rotation of the shoulder girdle, which may not be the most desired combination for people who lack adequate congruency of the scapulathoracic and glenohumeral joints. Most people complaining of shoulder pain tend to lack scapula control in the overhead position. Therefore rehabilitation and prehabilitation exercises that include isolated external rotation strengthening in certain angles may be of little value, because in most cases rotator cuff is a symptom rather than the cause. This does not mean that isolated rotator cuff strengthening exercises do not have a place in rehabilitation and performance setting, but it is rather important to look into the mechanical cause of the shoulder pain rather than attacking the symptom. This article will provide a brief insight on how the scapula controls the shoulder girdle during overhead movements, common scapula dysfunction associated in throwing and overhead activities and a simple basic assessment with a correction. There are myriads of factors that can contribute to shoulder pain such as cervical and thoracic impairments, rib rotation, breathing pattern impairment, trunk and lower extremity instability, structure of the acromion and other psychosocial considerations. However, these factors are beyond the scope of this article.
The role of scapula in overhead activities
Scapula plays a vital role in overhead movements. Lack of scapula upward rotation (60 degrees) during 180 degrees of shoulder flexion (overhead position) puts the humerus into a vulnerable position, as it is required to do excessive work in order to compensate for the lack of upward rotation of the scapula and hence inviting bigger muscles of the shoulders such as the deltoids to do the job. This scenario is far from ideal, as bigger powerful muscle such as deltoids can overpower some of the smaller, yet important muscles of the shoulders such as trapezius, serratus and rotator cuff group. This process, over a period of time can cause impingement to the shoulder girdle, as the bigger muscles tend to put a lot of resistance over the smaller muscles and thus offsetting their role. Therefore, assessing the scapula with regards to upward rotation is vital before prescribing corrective exercises. In some cases individuals with heavy arms and short trunk complain of shoulder pain, as the load of the arms pull the scapula downwardly and sometimes even tend to depresses the scapula, making it harder for the scapula to rotate upward or elevate.
Assessment and Correction
One of the simplest tests to assess scapula upward rotation dysfunction is the overhead shoulder flexion test. In most cases, people will either complain of pain as they go past 90 degrees of flexion, or simply cannot move beyond the 90-120 degrees shoulder flexion mark without arching the lower back or compensating from the cervical region (forward head). However, if the scapula is supported during the upward rotation phase of shoulder flexion then most people are able to achieve greater range of motion without pain. A simple wall slide test (face the wall, slide your arms resting as much weight against the wall as possible making the letter “Y” as you slide up, without shrugging the shoulders or arching the lower back) can be used to assess scapula upward rotation and in most cases can also be used as a corrective exercise for scapula upward rotation dysfunction. If doing this simple exercise reduces pain or increases range of motion of the shoulders compared to a normal shoulder overhead flexion movement, it is clear that scapula upward rotation is a major limiting factor in the shoulder flexion motion. The reason why sliding the arms may feel better as opposed to lifting arms overhead is because when we slide our arms against the wall, we reduce the role of gravity and hence the bigger powerful muscle such as deltoid do not have the mechanical advantage of offsetting the smaller muscles, this provides an opportunity for the scapula to rotate upward.
The role of the scapula is often underestimated when prescribing corrective exercises for shoulder dysfunctions. A thorough evaluation of scapula control, along with postural and movement impairments such as cervical, thoracic spine and the trunk is necessary to provide a detail corrective strategy. However, attention to detail in assessing the scapula upward rotation could help in providing better perspective in designing corrective strategies and exercise selection.
Designation: Strength and Conditioning Manager St Cuthbert’s College,
Strength and Conditioning Coach Pathway to Podium (High Performance Sport New Zealand, Aktive Auckland), and Short Course Lecturer Auckland University of Technology (AUT).
Education: Masters thesis in Sport and Exercise Science (Currently pursuing PhD in Sport science and exercise psychology). Australian Strength and Conditioning Accreditation level -2
Experience: 11 years (working with young, elite athletes and corporate clients, including athletes competing in Common Wealth Games, Olympic Games, World Cup Cricket under-19).