Water polo was among the first team sport in the Olympic Games in 1900 and is the longest running Olympic team competition (14,38). The game is typically played in a 30 by 20 m pool with a minimum depth of 2 m and seven players on a side participating at a time, including the goalkeeper. The object of the game is to score goals by forcing the ball into the opponent’s net. This must be done using one hand on the ball at a time (the goalkeeper may use two) while treading water. The opposing team may attack any player holding the ball, and the ball cannot be held underwater in an effort to keep it away from an opponent. The game is split into four 8-min quarters with a 30-s shot clock according to Federation Internationale de Natation (FINA) rules. Initial possession is determined after a “swim off” in which each team sprints to the center of the pool to reach the ball. There are three main types of fouls that may be committed during the course of the game (39). An “ordinary foul” or “minor foul” results from a rule infraction outside the 2-m line and results in a free pass. An “exclusion foul” is a major foul in which the offending player is excluded from the game for 20 s, giving the opposing team a “man-up” advantage. This typically results from attacking a player who is not holding the ball. A player who has been excluded three times in a game is excluded for the remainder of the game. A “penalty foul” is a type of major foul which results in a 5-m penalty shot. This occurs when a foul is committed within 5 m of the goal, preventing a probable goal. Another rare type of foul called a “brutality” occurs when a player demonstrates obvious intent to injure another player (37). These rules underscore the demanding, physical nature of this sport. Aquatic sport has the second largest athlete participation at the Olympic Games and water polo had the highest incidence of injuries of all the aquatic disciplines at two of the last three FINA World Championships (30). This article aims to review how best to care for these athletes and the unique group of illnesses and injuries they face (Table).
Water polo players can be prone to many of the same illnesses seen in other aquatic sports. A prospective study of 3 consecutive FINA World Championships demonstrated an illness incidence of 12.9/100 aquatic athletes (30). Most illnesses were infectious in nature, affecting either the respiratory tract or the gastrointestinal tract. Environmental exposure also was an important cause of illness contributing to 24.6% of illnesses with otitis and allergy/skin issues being most common. Consistently high illness rates were seen among water polo players when compared with other aquatic disciplines, possibly secondary to the close physical contact that the game requires. It also should be noted that this study took place during team travel for competition, which may further increase susceptibility to infectious illnesses.
Prolonged exposure to chlorine frequently causes eye irritation not seen in swimming due to the use of goggles, which are not allowed in water polo due to the risk of periorbital injury (34). The regular use of artificial tears can help prevent chronic conjunctivitis (7). Athletes who wear soft contact lenses also are at risk for pseudomonas infection and should be treated with fluoroquinolone eye drops if bacterial conjunctivitis is suspected (6,34). Acanthamoeba keratitis is a rare but serious condition, which also may be seen in contact lens wearers. Symptoms consist of eye pain and redness, blurred vision, light sensitivity, foreign body sensation, and excessive tearing. Early ophthalmology referral is key to identification and treatment of this condition (18,34).
“Swimmer's ear,” or otitis externa is common in water polo as well as swimming and is best prevented by regular use of acidic drops (7). Individuals with asthma, eczema, or allergic rhinitis are at highest risk because they are more prone to develop pruritis as a result of prolonged water exposure. Itching typically leads to scratching and frequent cleaning, causing a breakdown of the natural protective skin and wax barrier and allowing for infection, typically with Gram-negative bacteria such as pseudomonas. This is usually best treated by debridement and a combination of topical antibiotics, acidifiers, and corticosteroids. Keeping the ear dry helps prevent recurrent infection and is best accomplished by using a hair dryer and acidic drops, rather than swabs which can continue to break down the skin/wax barrier (27).
Although the use of sunscreen is advised during outdoor training, it should be kept in mind that application of greasy or slippery substances is not permitted during competition (7). These athletes can thus be at high risk of sunburn and other sun-related illnesses. In addition, water polo players are predisposed to a variety of dermatologic issues which arise as a result of the aquatic environment including swimming pool granulomas, “hot tub” folliculitis, molluscum contagiosum, and warts (34).
Asthma and exercise-induced bronchospasm (EIB) are more prevalent in aquatic sports (25). The prevalence in swimming appears to be significantly higher than in other aquatic sports disciplines; however, there is evidence to suggest that inhalation of chloramines, a byproduct of chlorinated pools, can increase the risk of airway hyperresponsiveness (28). The endurance nature of both swimming and water polo also may increase risk of EIB due to chronic inflammation and airway remodeling (25), and many children with asthma are steered toward aquatic sports due to the warm, humidified environment which is thought to be less likely to provoke bronchospasm (27). Clinicians caring for water polo players should be aware of the increased prevalence of this issue so that it can be recognized and treated appropriately with inhaled β-agonists and/or inhaled corticosteroids. Physicians prescribing medications for this condition should be familiar with the requirements of the World Anti-Doping Agency (WADA) because many of these agents require a therapeutic use exemption (TUE) to be used in competition (25,27).
Water polo players generally require a high-caloric diet to avoid energy balance issues. Consumption of 20 to 25 g of protein in the immediate postexercise period may help build lean muscle mass, which is important because a larger body mass can confer a physical advantage (4,11,34). As in other sports where a large muscle mass is advantageous, players should be educated about the risks of performance-enhancement products and how to avoid use of prohibited substances. Water polo players also should be monitored for mental health issues, because a recent study demonstrated increases in tension-anxiety, anger-hostility and fatigue-inertia after 2 months of training in experienced elite female water polo players (12).
Water polo players are at risk for both traumatic injury, due to intense physical contact, as well as overuse injury, due to vigorous training with repetitive throwing, swimming, and kicking (14). The majority of water polo injuries observed at the last three FINA World Championships occurred during competition with 10% to 23% of surveyed athletes reporting injuries (30). During the 2004 Olympic Games, one injury was recorded per two to three matches in men’s water polo. All injuries were contact related and two thirds resulted from “foul play”(19). This is very common in water polo; most “foul play” occurs under the surface of the water, making it difficult for referees to detect and regulate the very physical nature of the game.
Protective equipment in water polo is typically limited to mouth guards and caps fitted with ear guards. The use of protective eyewear without metal or sharp edges also is permitted (7). Only caps are mandatory. Mouth guards may be worn to protect from dental injury. A “nail check” also is performed before games to minimize the risk of laceration resulting from sharp fingernails or toenails. Adequate warm up is important for injury prevention, with lower-intensity passing drills being taught and performed before higher-intensity shooting drills. A recent study showed that in elite female water polo players, increased shoulder soreness is correlated with both increased shooting volume during training and less rest time between shots (41). This implies that there may be a role for monitoring shooting workload similar to pitch counts in baseball and underscores the importance of a training regimen which balances training and competition and incorporates adequate recovery time. A session RPE also has been validated for use in water polo training and also may help monitor workload to prevent overtraining and associated fatigue and decreases in performance (22). The addition of a sports-specific strength training program also may be helpful in injury prevention. In water polo, this program should focus on shoulder stabilization and leg strengthening, which can be performed in the water by holding weights overhead (34). Specific training focusing on the hip flexors and abductors and periodization of training also can help prevent the onset of fatigue-related changes in eggbeater kick which predispose to patellofemoral syndrome (29). Underwater grappling and kicking is common in water polo and can lead to injuries involving the abdomen and groin (34). This can be minimized by encouraging fair and safe play and encouraging referee responsiveness to these infractions, though they are often difficult to visualize from the pool deck.
Head and Face Injuries
The head and face are the most commonly injured body parts in water polo, usually as a result of physical contact (14,26). Contusions and lacerations are common, as well as eye injuries (7). There also is a risk of fracture to facial or orbital bones, particularly for the goalie who must attempt to block shots which are often released at speeds of up to 70 km ·h−1 (7,14). Concussions are of particular concern in water polo, with up to 36% of players reporting a history of prior concussion on a recent survey of USA Water Polo members and an average of more than two concussions per person. Goalies are again at particularly high risk, with 47% reporting at least one prior concussion (5). As in other sports, water polo players with suspected concussion should be removed from play and evaluated by a health care professional. Players who do undergo closed head injury in which there is an alteration of consciousness must rely on others to safely bring them out of the water for further evaluation — this is an important part of an emergency action plan. The presence of a certified lifeguard at practices and games helps to ensure that athletes unable to remove themselves from the pool can be removed in a safe and timely manner. A spine board should be available for use in any suspected spinal injury. Athletes who are ultimately diagnosed with concussion should undergo stepwise return to play under the supervision of a qualified physician and/or athletic trainer.
There are three main categories of eye injuries seen in water polo: corneal abrasions, hyphema, and blow out fractures (3,32). Corneal abrasions can be diagnosed using a fluorescein stain and a Wood’s lamp and typically require antibiotic eye drops. Hyphema, or blood in the anterior eye chamber, typically results from ruptured iris vessels and requires prompt ophthalmology referral. Blow-out fractures may result from direct trauma from a fist or ball. Clinically, this presents as a periorbital hematoma with a protruding or sunken eye, double vision on upward gaze and numbness of the cheek. Intraocular injury must be excluded, and surgical repair may be required (14).
Traumatic ear drum perforation also is common despite use of ear protectors (13). This typically occurs when a cupped palm slaps the side of the head, causing a sudden rise in pressure in the ear canal (14). The use of molded ear plugs and swim caps can help these players continue to train and play while minimizing water exposure and risk of infection, although ideally they should be kept out of the water (13,14).
Water polo is classified as a medium-risk sport for dental injury by the International Dental Federation (FDI); however, according to one survey only 7.7% of athletes wear mouth guards (16). Nearly 50% of those players reported having witnessed a water polo-related dental injury and 21% reported that they themselves had suffered a dental injury from the sport, most commonly a tooth fracture. It is unclear why despite these high injury rates so few players choose to wear protector gear. Mouth guards are not currently required by FINA, which is the international governing body for the sport. Avulsed teeth should be reimplanted as soon as possible. If it is not possible to reimplant the tooth immediately either saliva or cold milk make the best transport solutions if a specialty tooth storage solution is not available. The tooth should not be cleaned or scrubbed aside from gentle rinsing to preserve the root and periodontal ligament (21).
Upper Extremity Injuries
Water polo players are at unique risk for shoulder injury, and shoulder pain is the most common musculoskeletal complaint in these athletes (14). “Swimmer's shoulder” is common. This term was originally used to describe anterior shoulder pain during or after swimming due to repetitive subacromial impingement of the rotator cuff, specifically involving the supraspinatus tendon. This results from a combination of a hypermobile glenohumeral joint, multidirectional instability, scapular dyskinesis, and overuse-related fatigue (14,27). In addition, water polo is the only throwing sport in which water is the sole support base. In most throwing sports, force is generated through hip and trunk rotation and leg thrust against a fixed point. In water polo, not only is there not a fixed point to push off from but also rotation is typically limited by the defense (Fig. 1). This means that although the kinetic energy required to throw a water polo ball 40 mph is only 66% of what is required to throw a baseball 90 mph, an even greater proportion of that energy must be generated by the shoulder, and in particular the anterior shoulder stabilizers (10). These are the same muscles which generate much of the power for the freestyle stroke (31). The disproportionate strengthening of this muscle group leads to altered isokinetic torque ratios, similar to that seen in baseball. This imbalance may lead to abnormal shoulder mechanics, and in the setting of joint laxity may enhance subluxation during throwing. A dry land training program to strengthen external shoulder rotators may help counteract this imbalance and help treat and prevent shoulder injuries in this population (23). Due to the multifactorial nature of shoulder pain in these athletes, a comprehensive shoulder training program also should include strengthening of the scapular stabilizers and core musculature, as well as stretching of the posterior rotator cuff and capsule, scapular stabilizers, and pectoralis muscles (27). Athletes training through injuries should ensure a proper warm up and spend more time on lower-body exercises, such as eggbeater kick, while limiting swimming and throwing.
Rotator cuff injuries can vary from tendinopathy to complete tears, which are rare (10). In water polo, these injuries can be caused by a combination of overuse and trauma, as well as impingement. During the late cocking stage of the throw, the shoulder is held in extreme abduction and external rotation, which can result in internal impingement involving the posterior glenoid rim and the insertion of supraspinatus and infraspinatus tendons onto the posterior greater tuberosity (14) (Fig. 2). This position also is used at the start of the catch phase in freestyle swimming (10). The “head up” position in water polo eliminates the body roll normally used for this stroke, resulting in more forced abduction and even greater risk for posterior impingement and increased translation from rotator cuff fatigue (10). Most injuries involving the rotator cuff can be treated successfully with stroke modification and rotator cuff stretching and strengthening to correct muscle imbalances and altered biomechanics.
Traumatic shoulder injuries also may occur in water polo. Although physical contact can cause these injuries at any time, the shoulder is most vulnerable when held in the cocked position for passing or shooting. Direct contact in this position can result in anteroinferior glenohumeral subluxation or dislocation. Although posterior dislocation also can occur, this is seen less frequently (14). When it does occur, it typically results from the humeral head of a defender with a fully extended forward arm being driven backward by the rapidly moving arm of a shooting opponent (10). Acromioclavicular dislocations, or shoulder separations, also can occur via a similar mechanism. In this case, the scapula is driven backward until the clavicle contacts the ribs, after which, further posterior-directed force causes rupture of the acromioclavicular ligaments (10). Although most acromioclavicular dislocations respond well to nonoperative treatment, surgical stabilization should be considered to prevent recurrent injury in water polo players who experience glenohumeral shoulder dislocation.
The act of repetitive overhead throwing places water polo players at risk for elbow pain, similar to what is seen in baseball. The most commonly seen elbow issues in water polo include ulnar collateral ligament (UCL) injury, valgus extension overload syndrome, and osteochondritis dissecans of the capitellum (8).
UCL injuries typically result from valgus forces during cocking and acceleration which exceed the intrinsic tensile strength of the ligament (9). As with the shoulder, a higher proportion of force may be generated by the elbow in throwing than is typically seen in land sports due to the inability to use the ground as a leverage point. The water polo ball also is heavier and larger than what is typically used in other sports, again placing the elbow at a high risk for injury. Examination should focus on applying a valgus stress to the elbow to assess for laxity or loss of endpoint in a complete tear. This can be accomplished either by applying a direct valgus force to the elbow while held in 20 to 30 degrees of flexion, or by the milking maneuver in which valgus stress is applying by pulling the thumb with the shoulder in flexion and elbow flexed beyond 90 degrees with the forearm held in supination. Plain radiographs are useful for demonstrating an increase in medial joint opening in cases of instability, calcification of the ligament in chronic injury, or avulsion fracture of the sublime tubercle in acute-on-chronic injury, but magnetic resonance arthrogram has become the gold standard for confirming this type of injury, although ultrasound also has shown some promise (33). Nonoperative treatment consists of bracing to limit extension as well as strengthening of the flexor-pronator musculature before gradual return to throwing (15). Core and shoulder strengthening also may help decrease the amount of force transmitted to the elbow and improve neuromuscular control (17). Surgical reconstruction also may be considered for high-level athletes, or for those who have failed nonoperative treatment. Primary UCL repair is rarely an option, but may be possible in young athletes with acute avulsion injuries (15).
The valgus extension overload syndrome, or triple overload syndrome, results from medial elbow traction, lateral elbow compression, and impingement of the olecranon process in the olecranon fossa. Over time, this can lead to olecranon osteophytes which can be appreciated on plain radiographs using a Jones view in which the elbow is flexed to 110 degrees with the arm held flat on the cassette and the x-ray angled 45 degrees to the forearm (10). These athletes tend to have pain during the follow-through phase of the throw, when the elbow is in maximum extension. Nonoperative treatment is similar to that described above for UCL injuries, whereas operative treatment typically involves arthroscopy and osteophyte debridement (33).
Osetochondritis dissecans of the capitellum also can result from the valgus loading associated with overhead throwing in young athletes (8). In this injury, repetitive microtrauma to the capitellum may lead to microvascular injury and degeneration of subchondral bone. Although players with early, stable lesions may respond well to nonoperative treatment, advanced lesions may require surgical intervention with debridement, fixation, marrow-stimulating procedures, or osteoarticular autograph transfer (24,40).
Hand and wrist injuries also are common (14). Forcible abduction of two fingers can result in web space tears, which are the most common laceration in water polo (10,14). Mild injuries can be irrigated and closed, but more severe injuries involving the transverse metacarpal ligaments or collateral metacarpal-phalangeal ligaments may lead to instability and infection, requiring surgical debridement, reconstruction, and antibiotics. Unfortunately, these injuries have a high propensity to recur due to scarring and subsequent limited abduction after repair (10).
Dislocations also occur frequently, usually resulting from hyperextension of the proximal interphalangeal joint when a player tries to catch a ball or block a shot (1,14). Often, players will reduce these dislocations themselves, but they also may be associated with fracture of the middle phalanx, which may require surgical repair if greater than 40% of the articular surface is involved. Dislocation also may result from twisting of the fingers by an opponent in an attempt to escape the grasp of the affected player. This typically results in rupture of the collateral ligaments of the proximal interphalangeal joints and can be treated with “buddy taping” the affected finger to an adjacent one. Dorsal dislocations of the metacarpal-phalangeal joints are rare, but can be caused by the impact of the ball and may result in a “buttonhole” injury if the metacarpal head is caught between the flexor tendon and lumbrical tendon, trapping the volar plate in the joint. This injury requires surgical reduction (10).
The water polo ball has a very large circumference relative to other throwing sports: 68 to 71 cm for men, 65 to 67 cm for women (39). Controlling a ball this large requires players to hold their fingers in maximum abduction. A blow to the ball or a misjudged pass in this position can lead to injury to the UCL of the thumb or gamekeeper’s thumb (10). This ligament should be assessed for laxity and endpoint while held in extension and 30 degrees of flexion (35). Stener lesions in which the UCL is separated from the insertion point on the proximal phalanx by the interposition of the adductor aponeurosis require surgical stabilization, whereas partial tears may be treated with a waterproof thumb spica splint (2).
Fractures of the hand also are common in water polo, with metacarpal fractures being seen more commonly than phalangeal. These are best treated with custom-molded waterproof splints to allow players to maintain physical fitness with swimming until they can safely return to play (10).
Cervical spine pain is common. This typically results from degenerative and overuse type changes resulting from repetitive rotation for breathing and sustained periods of retraction and extension required to swim in the “head up” position to allow eye contact with the field of play (7). Disc injuries may lead to radicular symptoms in the upper extremities, as may acute acceleration/deceleration cervical spine injuries (7,14). This must be differentiated from traction neuropraxia, which also can be seen. Suprascapular nerve entrapment is rare, but is another important cause of upper extremity weakness. This injury can be gradual in onset, resulting from tethering and chronic irritation in the suprascapular notch or along the scapular spine due to increased scapulothoracic motion associated with throwing. Weakness is present in the supraspinatus or infraspinatus and the athlete often complains of a vague, diffuse, deep posterior shoulder pain. Imaging and/or nerve conduction studies may help differentiate between these various causes of neurologic complaints. Plain radiographs with Stryker notch views of the shoulder may demonstrate a calcified superior transverse scapular ligament, or a narrow suprascapular notch. This type of injury may require surgical decompression (10). Though not discussed in detail here, thoracic outlet syndrome also is seen in swimmers and overhead athletes and should be considered as part of a differential diagnosis for radicular symptoms. Although rare, acute cervical spine injury also is possible, either from direct contact with an opponent, or with the bottom of the pool after diving into the water. Athletes with a suspected acute cervical spine injury should be carefully removed from the water by a certified lifeguard.
Lumbar spine pain also is common (7,14). Significant rotational force is required for throwing and passing, placing stress on the lumbar spine. The most common pain generators in these athletes include the intervertebral discs and the apophyseal joints (20), although acute muscle strains and nerve compression due to disc herniation also are possible. Correction of intervertebral segmental hypomobility may be helpful in decreasing symptoms, as well as anti-inflammatories, massage, dry-needling, and neural stretching techniques (14). Ensuring adequate core strength also can help alleviate the stress placed on the lumbar spine and intervertebral discs. For any spinal injury, it is important to be aware of any “red flags” that indicate need for urgent evaluation with possible neuroimaging. These include fevers, bowel or bladder dysfunction, and progressive neurologic deficits.
In water polo, the eggbeater kick is commonly used to maintain an above surface play position, propel through the water, and accomplish water polo maneuvers (27) (Fig. 3). This is the main cause of lower-extremity injuries in water polo. In this kick, the left leg rotates clockwise while the right leg rotates counterclockwise producing a compressive force on the medial knee, similar to that seen in breaststrokers. Over time, this can lead to medial collateral ligament (MCL) laxity and degenerative changes, including meniscal tears (7). Repetitive use of this kick also has been referenced as a cause of patellofemoral syndrome. Water polo players with knee pain may benefit from strengthening of the hip flexors and abductors to decrease fatigue-related changes in kick performance which may contribute to these types of injuries (29). Hip adductor strain also may be seen as a result of the kick and should be treated with stretching and strengthening of the involved muscle group (7).
Lacerations are common, especially supraorbital facial lacerations. When possible, it is best to avoid the use of sutures to allow return to play. Ideally, wounds should be thoroughly cleaned and closed using dermal glues and adhesive strips. Plastic-based waterproof antiseptic spray also may be helpful (7). Players with actively bleeding wounds are not allowed to return to the field of play.
Water polo is a unique team sport that is growing in popularity according to the most current annual reports from USA Water Polo (36). Health care providers caring for these athletes should be equipped with a basic understanding of the game, as well as the unique illnesses and injuries these athletes face. Although water polo players face many of the same issues as swimmers with respect to exposure to chlorinated water, they are more prone to related illness due to limited eye protection. They also are more prone to sun-related injury due to an inability to wear greasy sunscreens in competition. In addition to the shoulder injuries commonly experienced by swimmers, water polo players also face the injuries seen in other throwing sports, including elbow injuries. Finally, it is important to recognize the very physical nature of the game, due in part to limited protective equipment, as well as a limited ability to referee the “foul play,” which often occurs underwater. Health care providers covering this sport need to be prepared to see a wide variety of injuries in a unique environment. Having a certified lifeguard present to remove seriously injured players from the water is crucial, as is an understanding of how these players can be treated for injuries in a manner that allows them to return to the water as soon as it is safely possible.
The author declares no conflict of interest and does not have any financial disclosures.
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