Introduction
The Federation Internationale de Volleyball estimates that 500 million people play volleyball worldwide (26). The greatest area of the growth has been in beach volleyball, which is played on the sand with two people on each side rather than six on each side as in indoor volleyball. Both beach and indoor volleyball are Olympic sports and watched by many.
Injuries in volleyball are commonly due to jumping and landing as well as from hitting and blocking the ball. The ball can reach speeds of 80 mph and can cause significant injury should the ball strike an unintended area of a player’s body. Certain positions are associated with specific injuries (Table). More injuries occur during hitting and blocking than during passing or setting. Most injuries, whether acute or overuse in nature, occur during the act of jumping. Overuse injuries are somewhat more common than acute injuries and are due to faulty technique, amount of repetition, or type of playing surface. Elite athletes are at greater risk of overuse injuries, presumably due to more hours of practice.
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Table: The function(s) of each type of player in indoor volleyball and the injuries associated with that position.
Beach volleyball has a different injury pattern than indoor volleyball. There are more overuse injuries of the shoulder in beach compared with indoor volleyball (1), which is thought to be due to more frequent serves and hits because of fewer players per team. There are a lower number of ankle sprains in beach volleyball (6), which also may be related to the small team size, since with fewer players on the court, there is less chance of landing on someone else’s foot. There is a lower incidence of patellar tendinitis in beach volleyball compared with indoor volleyball. This may be because the player cannot jump as high in sand (7) so there is less of an eccentric quadriceps load upon landing. The sand provides a softer landing surface, which also puts less eccentric load on the quadriceps tendon.
Ankle/Foot Injuries
Ankle Sprains
Ankle sprains are the most common acute injury in volleyball, with one study showing these accounted for 41% of all volleyball-related injuries (35). These usually occur when landing onto another player’s foot, often a player from the opposing team, so these are more common in positions that play around the net. When evaluating a sprained ankle in a volleyball player, there is usually evidence of injury to the lateral ankle with swelling and tenderness. It is important to not miss a fracture, as the treatment would be likely different. The Ottawa ankle rules can help the clinician decide when a fracture could be present and radiographs necessary (31).
The initial treatment of ankle sprains is elevation, icing, and protected weight bearing with a stirrup-type brace. This limits the amount of swelling which develops and allows protected motion while the ligament heals, ultimately allowing quicker return to play (RTP). When the pain diminishes, rehabilitation usually is carried out by a physical therapist or athletic trainer with exercises to regain ankle motion, peroneal strength, and proprioception. Cross-training can be employed while healing takes place. In the latter stages of rehabilitation, the athlete should reintroduce jogging and then drills specific to volleyball such as hopping, cutting, and lateral shuffles.
Recurrent sprains are common, with one study showing a 42% risk of resprain in volleyball players within 6 months of the initial sprain (5). This emphasizes the importance of completing a supervised rehabilitation program before returning to play. Balance board training to regain proprioception has shown to be effective in preventing recurrences of ankle sprains in volleyball players (34). Wearing a lace-up ankle brace or taping the ankle for the remainder of the season also may help reduce the incidence of recurrent sprain.
Achilles Tendinopathy
The paratenon of the Achilles tendon may become inflamed 2 to 6 cm above the calcaneal attachment site, called Achilles tendinitis. This is common in sports like volleyball where there are repetitive eccentric loads to the Achilles tendon from jumping and landing. There is tenderness and sometimes crepitus of the tendon. Initial treatment consists of rest from painful activities, ice, and anti-inflammatory medications. Rehabilitation consists of stretching, progressive strengthening, and gradual return to activities.
The Achilles tendon also can develop a degenerative condition known as Achilles tendinosis. This term is used rather than tendinitis because the primary pathology is tendon degeneration rather than inflammation. This condition tends to occur in older players and is usually chronic and difficult to treat. They have a thickened and often nodular tendon with variable amounts of tenderness. Activity modification, heel lifts, and stretches may be tried. In cases resistant to conventional treatment, heavy-load eccentric calf muscle training has been shown to be helpful (2). In addition, if the Achilles tendon is tight, wearing a splint at night which keeps the ankle in 5° dorsiflexion may be helpful. Some recent studies have shown also shock wave treatment to be effective (14,28). A recent study found no clinical benefit of platelet-rich plasma injection over placebo injection when added to an eccentric training program in chronic Achilles tendinopathy at 1 year (9). Surgery can be considered if symptoms are disabling despite 6 to 12 months of nonoperative treatment.
Sand Toe
Since beach volleyball is played barefoot, the toes are vulnerable to injury. In “sand toe,” the great toe becomes caught on the sand and the first metatarsophalangeal joint becomes hyperplantarflexed, injuring the dorsal capsule. In addition, the plantar base of the proximal phalanx can become compressed into the metatarsal head, causing bony injury. This injury compromises push-off, running, and jumping. The initial treatment is ice, rest, and nonsteroidal anti-inflammatory drugs. Wearing a pair of shoes with stiff soles or orthotics fabricated with rigid carbon fiber will help limit the motion of the injured joint. Later, toe strengthening exercises can be employed. When returning to play, taping the toe with a moleskin checkrein on the dorsal and plantar aspects can limit the first metatarsophalangeal joint motion and protect the toe. This condition may take as long as 6 months to recover fully.
Knee Injuries
Patellar Tendinopathy
Explosive and repetitive jumping is important to success in volleyball and can lead to pain in the patellar tendon. An estimated 40% to 50% of high-level volleyball players develop patellar tendinitis at some point (23). Risk factors for patellar tendinitis in nonelite athletes are male sex, higher body weight, and taller stature (37). The most common site of pain is where the patellar tendon attaches to the inferior pole of the patella. There is point tenderness at this site that distinguishes it from patellofemoral syndrome, another common source of anterior knee pain in athletes. Treatment is similar as described for Achilles tendinitis.
The patellar tendon also can become degenerated and painful, a condition called patellar tendinosis. This tends to be resistant to treatment and recurrent. The volleyball player may have to take a considerable period of rest from jumping to allow the pain to subside. Rehabilitation consists of stretching of the musculotendinous unit and then strengthening. As the condition improves, eccentric closed chain strengthening is carried out. One study showed more improvement if the eccentric squat exercise was done on a decline board at 25° versus being done on a 10-cm step (36). For recalcitrant cases, some studies have reported positive results with dry needling and injections of autologous blood or platelet-rich plasma (32). Some studies also have shown extracorporeal shock wave therapy to be safe and effective, but the studies were not of high quality (33).
Anterior Cruciate Ligament Injury
Anterior cruciate ligament (ACL) tears are not as common as patellar tendinitis but are a much more serious injury. It is well recognized that they occur at a considerably higher rate in women than men in landing and cutting sports (18). In addition to female gender and prior ACL tear, a number of risk factors have been proposed including intercondylar notch width, generalized ligamentous laxity, and increased body mass index (15). In volleyball, the mechanism for ACL tear usually is coming down awkwardly from a jump or a cutting maneuver. The athlete is almost always unable to continue playing after sustaining this injury. Swelling typically develops within a couple of hours. The Lachman test is usually diagnostic, provided that the patient is able to relax their muscles. Magnetic resonance imaging (MRI) is often performed to confirm clinical suspicion and look for concomitant injury.
Most people who wish to return to a sport like volleyball will opt to have the ligament reconstructed. The surgery is quite successful in yielding a stable knee and thereby decreases the chance of subsequent meniscal tears; however, many are not able to return to their previous level of play. One study showed that less than 50% of athletes returned to playing sports at their preinjury level or returned to participation in competitive sport when surveyed 2 to 7 years after ACL reconstruction (3). Given that many athletes are not able to return to high-level sports and the increased risk of osteoarthritis after an ACL tear, there has been considerable emphasis placed on prevention programs. There have been numerous studies looking at proprioceptive and plyometric training programs to decrease ACL injury risks in athletes engaging in sports with cutting, jumping, and sprinting, with many showing encouraging results. (16,21). One study included female volleyball players and showed that a neuromuscular training program significantly reduced ACL injuries (17).
Shoulder Injuries
Shoulder Instability
The arm swing during a volleyball overhead serve and spike traditionally has been thought of to occur in three phases: cocking, acceleration, and deceleration/follow-through (13). To forcefully hit an unreturnable ball to the opponent’s side of the court, the hitter’s arm goes into an extreme external rotation and extended position during the late cocking/early acceleration phase (Fig. 1). This position levers the humeral head anteriorly on the glenoid and may result in pain and/or a feeling of shoulder instability. The function of the rotator cuff is to restrain excessive movement of humeral head and also assist in internally and externally rotating the humerus. The most common cause of shoulder pain in volleyball players is overuse of the rotator cuff, which is understandable given the typical volleyball hitter/server hits the ball thousands of times in a typical season. Shoulder pain also may be due to a variety of other pathologies such as tearing of the inferior glenohumeral ligament or the labrum. Treatment involves strengthening of the rotator cuff, which limits the amount of anterior subluxation of the humeral head and provides endurance.
Figure 1: Extreme external rotation and extension of the arm just before contact with the ball in a professional beach volleyball player (photo courtesy of Holly Flanders).
The athlete also may experience internal impingement when the rotator cuff and labrum become impinged at the posterior superior aspect of the glenohumeral joint as a result of anterior subluxation of the humeral head (10,19). This pain is felt usually at the posterior aspect of the shoulder. On examination, the pain is reproduced by placing the arm in a cocked position and often alleviated with a relocation maneuver (posterior directed force to the humeral head). The initial treatment is rotator cuff strengthening as mentioned.
Hitters and servers who have a long history of repetitively placing their shoulders in extreme external rotation may develop where there is limited internal rotation of the shoulder compared with their nondominant side, a condition known as glenohumeral internal rotational deficit (24). This is due to contracture of the posterior capsule of the joint and may result in obligatory posterosuperior shift in the humeral head during the cocking position, which is associated with a variety of painful shoulder conditions such as internal impingement, external impingement, and labral tears. If symptomatic, treatment involves stretches of the posterior capsule using “sleeper stretches” (4) (Fig. 2).
Figure 2: Sleeper stretches: A. The patient lies on their side with the involved arm against the table and the shoulder and elbow flexed to 90°. B. The patient pushes their forearm toward the table with the opposite hand, maneuvering the arm into internal rotation thereby stretching the posteroinferior capsule. (Reprinted with permission from Burkhart SS, Morgan CD, Kibler WB. The disabled throwing shoulder: spectrum of pathology. Part III: The SICK scapula, scapular dyskinesis, the kinetic chain and rehabilitation. Arthroscopy. 2003; 19(6):641–61.)
The scapula must not be overlooked in patients with shoulder pain. Malpositioning of the scapula can contribute to impingement. Weak periscapular muscles can alter shoulder kinematics and, in turn, lead to shoulder pain. For these reasons, therapy of shoulder problems should always include scapular stabilizing exercises.
Suprascapular Neuropathy
The suprascapular nerve first travels through the suprascapular notch at the superior aspect of the scapula and then goes on to innervate the suprascapular muscle. The nerve continues and passes through the spinoglenoid notch at the lateral aspect of the scapular spine and then innervate the infraspinatus muscle. The nerve can become entrapped at both locations, but it is at the spinoglenoid notch that volleyball players are particularly vulnerable. Studies have shown that anywhere from 12% to 30%, top level volleyball players have infraspinatus muscle weakness and atrophy (11,22). There are various theories as to the mechanism of injury to the nerve (12,30). It is generally thought to occur from traction and/or compression of the nerve during the extreme motions of the arm during the cocking or follow-through phases of the arm swing while serving and hitting. The “float serve,” which involves a strong eccentric contraction of the infraspinatus, is also postulated to cause traction of the nerve (12). Less frequently, the nerve also can be compressed at the notch by a ganglion emanating from a tear of the posterior superior labrum. Also in the differential diagnosis of suprascapular neuropathy is the Parsonage-Turner syndrome (brachial neuritis).
Suprascapular nerve palsy is occasionally associated with posterior shoulder pain, but usually the muscle atrophy and weakness are just incidental findings and the external rotation weakness does not affect their play. The reason this is tolerated so well is that external rotation strength is not near as important to performance in volleyball as internal rotation strength. In addition there is compensation by the teres minor muscle, another external rotator of the humerus, which is innervated by a branch of the axillary nerve.
Electromyography usually will confirm the diagnosis but is not necessary in most cases. The electromyography can be repeated at 6 months, if done initially, to assess recovery. If the player is symptomatic, the treatment consists of temporarily limiting overhead hitting and physical therapy to strengthen the rotator cuff and periscapular muscles. Most cases respond to nonoperative treatment but may take up to a year for maximal recovery. If the patient is not improving or has significant initial disability, consider obtaining an MRI to look for a possible ganglion compressing the nerve. A newer imaging technique called magnetic resonance neurography may show abnormalities in the affected suprascapular nerve and denervation changes in the corresponding muscles (8). Surgery can be considered if there is a space-occupying lesion on MRI or if there is significant pain and decreased performance despite 6 months of the mentioned treatment. Interestingly, after successful treatment and resolution of symptoms, the infraspinatus atrophy often persists.
Hand/Wrist Injuries
Sprains, Fractures, and Dislocations
Traumatic injuries to the fingers are common in any ball-handling sport, and volleyball is no exception. Blockers are especially vulnerable to injury from axial loads to the fingertip and hyperextension of the finger from the ball. Hitters can get finger injuries if they hit the net or another player during the follow-through phase of the swing. Radiographs are warranted for most finger injuries to rule out fracture or dislocation. Most finger injuries involve ligamentous injury to the proximal interphalangeal (PIP) joints of the fingers. They usually respond to brief immobilization followed by buddy taping and early RTP. Sprains to the metacarpophalangeal joint of the thumb often take longer to RTP especially in an overhead setter. Thumb spica taping or splinting may allow sooner RTP. More significant injuries of the PIP joints that should not be missed are large fractures of the volar base of the middle phalanx and central slip ruptures.
Most finger dislocations occur at the PIP joint in a dorsal direction and are easily reducible after radiographic confirmation. Finger fractures that are displaced or unstable warrant consultation with an orthopedic surgeon. Most finger fractures and dislocations take closer to 1 month to RTP depending on the position played and hand dominance.
The mallet finger usually is thought of as a baseball injury but can affect volleyball players when the ball hits the fingertip. With this injury, the distal phalanx is forced into flexion, rupturing the extensor tendon. This results in a flexed distal interphalangeal (DIP) joint, which the player is unable to extend actively. The treatment is continuous splinting of the DIP joint in extension for 6 to 8 wk, during which time the extensor tendon scars back down to the proximal aspect of the distal phalanx. This treatment is highly successful. One study showed 90% patient satisfaction rate at 5-year follow-up and average DIP joint extension deficit of only 8.3° with little evidence of functional impairment (25).
De Quervain Tenosynovitis
During a serve return, the ball typically impacts the volar aspects of the forearms. If the ball is received incorrectly repeatedly at the volar radial aspect of the wrists, the synovium of the sheath of the first dorsal compartment of the wrist can become inflamed, a condition known as de Quervain tenosynovitis (29). On examination, there is tenderness over the compartment and pain with Finkelstein test. This test is performed with the thumb inside the fisted hand and passive ulnar deviation of the hand. The initial treatment is ice, nonsteroidal anti-inflammatory drugs, and avoiding further ball impact at the site. Use of a thumb spica splint while not playing may be helpful also. If symptoms are severe upon presentation or persist despite the mentioned treatment, a steroid injection into the sheath is usually highly effective. A review showed an 83% cure rate with injection alone (27). Recurrence can be prevented by adjusting the area of ball impact to the correct position on the volar aspects of the forearms.
Low Back Pain
Underhand passers are susceptible to low back pain (LBP) due to repetitive lumbar flexion. The upper extremities held in front of the body act as a long lever arm placing considerable strain on the low back. Passers also are susceptible to LBP when they must repetitively rotate at the trunk to accept high-velocity jump serves from the side, when they do not have enough time to get in front of the ball.
Spondylolysis
Spondylolysis is a stress fracture at the pars interarticularis of a lower lumbar vertebra (the fifth lumbar vertebra is the most common). When a player hyperextends the low back when hitting (Fig. 1) or when “back setting,” there is considerable shear forces placed on this portion of the vertebra. When performed repetitively, a stress fracture can develop. Adolescents are especially vulnerable to this injury because their vertebrae are still weak at the pars. On examination, the athlete experiences pain to the side of a lower lumbar vertebra upon extension.
Radiographs are obtained initially to look for a pars fracture. If this shows a fracture, the condition is usually chronic and there is little chance of healing. If a fracture is not seen, an MRI or bone scan with single-photon emission computed tomography (SPECT) is performed. If there is activity (increased uptake) in the pars on the SPECT or edema on MRI, there is potential for healing. Patients must limit extension activities for at least 6 wk. Also the core is strengthened and the hamstrings are stretched. Consideration may be given to a rigid lumbar orthosis, which helps reduce motion of the lumbar spine. There is no agreement on the specific indications for a lumbar orthosis or the duration of use.
If the stress fracture has not healed at 4 months despite what was mentioned, a bone stimulator can be considered. Healing rates depend on many factors including the duration of the lysis, whether it is unilateral or bilateral, the width of the fracture line, and the activity of the fracture on the SPECT. There is no consensus in the literature on the healing rates, but it has been estimated that 75% to 100% of acute lesions heal, 50% of early bilateral lesions heal, and no chronic defects heal (20).
In established pars fractures, where the defect is seen on radiographs and/or there is lack of activity on SPECT or MRI, union of the fracture is not achievable. Painful flares are treated symptomatically with relative rest, avoidance of lumbar extension, and wearing a lumbar orthosis until the pain subsides. Keeping the core strong may decrease future episodes of pain. Even though bony healing will not occur, fibrous union of the pars defect often occurs and can lead to improvement in pain. If there is an established pars defect bilaterally, spondylolisthesis may occur. A slip of greater than 50% or development of neurologic symptoms warrants surgical consultation.
Conclusions
Interest in volleyball has flourished, and it is now one of the most popular events in the international sports world. While enjoyable, injuries can occur from frequent jumping as well as from hitting and blocking the ball. Injuries can be either acute or repetitive in nature. Injuries typically involve the ankles, knees, and shoulder. With an accurate diagnosis by a sports clinician, appropriate treatment can commence and often the player can return to training and competition with minimal downtime.
The author thanks Aresio Souza for reviewing this manuscript.
The author declares no conflict of interest and does not have any financial disclosures.
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