Kevin E. Wilk, PT, DPT, FAPTA, Christopher A. Arrigo, MS, PT, ATC,   

Todd R. Hooks, PT, AT, OCS, SCS, NREMT-1, CSCS, CMTPT, FAAOMPT, 

James R. Andrews, MD 

 Summarized by Kaytlyn Wells SPT, Missouri State University, Springfield, MO. 

The purpose of this article is to demonstrate why the whole body and the kinetic chain must be addressed when treating a symptomatic shoulder in overhead (OH) athletes. These athletes typically demonstrate anatomical adaptive changes due to the repetitive nature of OH motions. These include osseous structures, soft tissue structures, posture, and hip joint abnormalities. Common abnormalities in contractile tissue include: hip, serratus anterior, low-mid trap, and all other periscapular musculature. This is likely due to the eccentric control of this muscles during the acceleration phase of throwing. All areas listed for adaptive changes are things to consider with a rehabilitation program for OH athletes. The foundation of a rehab program should include the following: mobility, stability, scapular mechanics, dynamic stability, and neuromuscular control, as well as strengthening of the core, hips, and legs.  

Wilk et. al., outlined a multi-based rehab approach including 4 steps. The goal of these are to progressively return athletes to play. Each phase builds on the last while still maintaining principles learned in the prior phase. The goals of the approach are used to address the 5 foundational components as previously listed. To advance the athlete to a new phase, one must use their best clinical judgement as the athlete meets the goals per phase.

During Phase I, the acute phase, the goals are that of any rehab program; to reduce pain and inflammation, restore motion, address postural imbalances, improve stability and neuromuscular control, and to control functional stress and strain of the periscapular and shoulder musculature.  

During Phase II, the intermediate phase, the goals are similar but progress towards strength exercises, restoring muscular balance, enhancing dynamic stability, and addressing flexibility. The “Throwers 10” is added here to address all of these areas with the addition of scapular mechanics and control. The scapula is one of the most important components of this rehab due to its function as it provides optimal stability and allowing for distal mobility. Allowing for the upper extremity, core, and lower extremity to work together is vital to prepare the athlete for sport like conditions. Plyometrics are also a huge component of this phase and helps with proprioception, helping overall neuromuscular reeducation of the periscapular musculature.  

Phase 3 is the advanced strengthening phase and the primary focus is to aggressively strengthen, furthering neuromuscular control, while focusing on strength, power, and endurance for optimal, prolonged performance. This phase utilizes functional drills in bilateral, followed by unilateral upper extremity to help target endurance. Another focus is to continue addressing neuromuscular control of shoulder girdle and rotator cuff. Again, these phases and the athletes rehab should focus on total body exercises to allow the entire kinetic chain to function together as one unit instead of segmentally. This phase is also going to introduce the interval throwing program (ITP). Throwing will be done in 2 phases, the first being in this phase and the second in the final phase. In phase one of the ITP, the athlete will throw long toss starting at 45 feet and then increasing. This throw is to be done at low velocities as it is designed to be a transition from rehab to performance.

  Phase 4 is a return to throwing phase. It takes everything from the first 4 phases and builds upon it. Mechanics of throwing are highly important here as the athlete progresses to 120 to 180 feet for pitchers and position players, respectively. Return to play is assessed here and requires specific criteria to be met. This includes the following: full non-painful range of motion, full muscle strength, satisfactory shoulder exam, successful completion of the throwing program without pain while exhibiting proper throwing mechanics, and lastly, satisfactory shoulder subjective scores.  

In summary, the overhead athlete may demonstrate joint laxity, hypomobility, strength deficits, altered ROM (mostly lacking IR), postural abnormalities, and osseous adaptations due to the repetitive nature of throwing. Any rehab program should address shoulder stability and include a resistive exercise program to fully restore strength and endurance in periscapular musculature. The program should also focus on linking the upper extremity, core, and lower extremity utilizing strengthening and plyometric exercises. 

Personal Commentary: 

The shoulder is something that has honestly always terrified me due to the complexity of the joint, in addition to this being the first joint we covered in PT school. I was a bit overwhelmed to really absorb the material. However, I love the biomechanics and complexity of throwing and the many different variables that can influence the overall pitch/throwing performance. During my third clinical rotation, I worked with many patients with shoulder pathologies which intrigued me even more. Upon reviewing this article, my understanding of the importance of so many factors greatly improved. I want to have my own practice where I work with athletes, so this article will be of benefit in guiding my treatment plans with the OH athlete.  

 This article nicely correlates with “The Slide”…the IAOM-US diagnosis and treatment model. Initially the primary goal with OH athletes with this program described by Wilk et al is to reduce pain and also address the any segmental movement dysfunctions in the shoulder girdle in order to prepare for feedforward and feedback neuromuscular training. These athletes require special attention as they prepare for the functional integration program. Near the end of phase two, Wilks et al transitions towards performance enhancement to also address the entire kinetic chain, correlating nicely to the IAOM model of further strengthening (fundamental performance) to advanced performance incorporating the entire body and then sport specific task advancement. 

There is a magnitude of evidence to support the claims by Wilks when suggesting that shoulder rehab is more than just external and internal rotation strengthening. The scapula is an area commonly under-functioning in these OH athletes. Kibler describes the importance in scapular function by stating “The scapula’s various roles are concerned with achieving [normal] motions and positions to facilitate the efficient physiology and biomechanics to allow optimum shoulder function. The failure of the scapula to perform these roles causes inefficient physiology and biomechanics and, therefore, inefficient shoulder function. This can cause poor performance and can cause or exacerbate shoulder injury.” By addressing the scapula, this allows the entire shoulder to function as it was designed with maximum efficiency and a greatly reduced risk of injury.  

As strongly illustrated in the above article, the kinetic chain and involvement of full body incorporation is also a vital function in returning athletes to sport. McMullen et al., states, “This model illustrates the contribution of the entire body during sport activities rather than focusing on the action of individuals segments. Normal, efficient motion and muscle activation are believed to occur in proximal to distal sequence. This proximal-to-distal sequence should be considered when attempting to restore function via the rehabilitation protocol.” Furthering the evidence for the need for a whole body approach is demonstrated McMullen et al. He states that “Full arm elevation requires full scapular retraction, which requires spinal extension, hip extension, and so on. The large muscles of the hips and trunks thereby help position the thoracic spine to accommodate appropriate scapular motion.” The articles by McMullen help to support the idea of addressing the entire kinetic chain when rehabbing shoulder injuries as does Wilk et al. 

As we were taught in PT school, we should not only initially treat the lesion, but look up and down the chain for causal implications to promote return to full function and wellness. Due to the complexity of throwing, a misstep, altered hip mechanics, lack of thoracic rotation can cause altered biomechanics of the shoulder, leaving it susceptible to injury. 

References: 

  1. McMullen, J., & Uhl, T. (20n.d.). A Kinetic Chain Approach for Shoulder Rehabilitation. Journal of Athletic Training, 35(3), 329–331. 
  2. Kibler, B. (1998). The Role of the Scapula in Athletic Shoulder Function. The American Journal of Sports Medicine, 26(2).