Many sport enthusiasts consider water polo to be much like rugby in a swimming pool. Water polo combines swimming and throwing while simultaneously involving high levels of contact between players. It is an extremely physically demanding sport that incorporates intense bursts of activity with steady moderately intense activity, all while staying afloat. Water polo results in many acute injuries including concussion and many facial, spinal, upper and lower extremity injuries. Signs of water polo injuries include inflammation, pain, lacerations of the skin, joint instability, limited flexibility, and decreased range of motion. This article will focus on the most commonly injured joint in water polo: shoulder injuries.
It is important to understand the mechanics of throwing a water polo ball to understand the types of injuries that result. There are three phases of the throw that include the wind-up with transition from early to late cocking, acceleration and deceleration.
The wind up involves preparation for the throw, as the arm is pulled backwards and overhead while the trunk rotates. The shoulder specifically goes through abduction and external rotation, with the elbow at 45 degrees to maintain stability of the ball. During early and late cocking the body is at peak activation as the player is freely floating in the pool and not allowed to have the support of the ground for stability while throwing. In addition, this phase generates maximum shoulder rotation and torque with emphasis being placed on the deltoid.
During the acceleration and deceleration phases the shoulder maintains 90-degree abduction as the ball is propelled and leaves the hand. Throughout acceleration the triceps, pectoralis major, serratus anterior, and latissimus dorsi are activated to move the arm forward. The deceleration phase is characterized by muscle activation to slow the arm after release of the ball. Throughout deceleration theshoulder experiences maximum internal rotation with eccentric contraction, whichis what sets up for shoulder injury and overuse. In addition to muscle hypertrophy to slow the arm movement, there is also compensatory tightening of the posterior shoulder capsule and a propensity to develop excessive external rotation (or loss of internal rotation, known as glenohumeral internal rotation deficit or GIRD).
There are many potential shoulder injuries that can be sustained while playing water polo including “swimmer’s shoulder,” shoulder (subacromial) impingement, SLAP tears of the labrum, rotator cuff injuries, and even shoulder dislocation.
Swimmer’s shoulder is a common overuse injury, not just due to throwing the ball but results from swimming overuse, as the name implies. Shoulder impingement and bursitis typically occur to the subacromial bursa and can be either internal or external rotation in origin. SLAP tears of the labrum are typically manifested during the acceleration phase of throwing, much like occurs with baseball players. Rotator cuff injuries range from simple inflammation (tendinitis), chronic inflammation (tendinopathy) to tears (partial or complete), and are more common because of the development of GIRD, improper throwing mechanics, and weakness of the periscapular muscles (scapular dyskinesia). All of these shoulder injuries can be mitigated through appropriate strengthening, stability training of the shoulder girdle muscles, and throwing mechanics analysis and correction.
By: Lin Ozan & Jon Minor, MD
References
Common Injuries in Water Polo. Physio Works. Water Polo Injuries 2017.
Zoe Russell. Accessed on 0ctober 31, 2017 at
http://physioworks.com.au/Injuries-Conditions/Activities/water-polo-
injuries
Injuries in Water Polo. M. Franic, A. Ivkovic, and R. Rudic. Croat Med F. 2007
June; 48(3): 281-288.
Stop Sports Injuries. Preventing Water Polo Injuries 2017. American Orthopedic Society for Sports Medicine. Accessed October 31, 2017 at http://www.stopsportsinjuries.org/STOP/STOP/Prevent_Injuries/Water_Po lo_Injury_Prevention.aspx
Water Polo Injuries 101: Identifying and Healing with Physical Therapy. COR
Accessed on October 31, 2017 at https://www.trainingcor.com/water-polo-injuries/
Images
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