Throwing injuries of the upper extremity: Treatment, follow-up care, and prevention

INTRODUCTION — Millions of people throughout the world participate in sports that involve throwing or throwing-like movements. Such athletes are susceptible to a number of shoulder and elbow injuries due to the stresses involved in throwing.

The treatment and prevention of throwing-related upper extremity injuries in adults and older adolescents is reviewed here. The presentation and diagnosis of such injuries and the assessment of children with elbow or shoulder injuries are reviewed separately. (See "Throwing injuries of the upper extremity: Clinical presentation and diagnostic approach" and "Throwing injuries: Biomechanics and mechanism of injury" and "Elbow injuries in active children or skeletally immature adolescents: Approach" and "Evaluation of acute traumatic shoulder injury in children and adolescents".)

INITIAL TREATMENT — The initial treatment for most throwing injuries is relative rest. This involves significantly decreasing the number of throws performed by an athlete or eliminating throwing altogether for a period. For a baseball pitcher or catcher, this may be as simple as changing positions, ideally to first base or designated hitter. For position players who do not throw as often, depending on the severity of the injury, a position change or elimination of throwing during practice may be required. Complete cessation of throwing is often necessary if an injury is severe.

Immobilization is rarely needed and may be detrimental. Pain can generally be managed with acetaminophen or a short course of nonsteroidal antiinflammatory drugs (NSAIDs). The possible effects of NSAIDs on soft tissue healing are reviewed separately. (See "Nonselective NSAIDs: Overview of adverse effects", section on 'Healing of musculoskeletal injury'.)

TREATMENT OF SPECIFIC INJURIES

Shoulder conditions

Rotator cuff injuries — The majority of rotator cuff injuries may be treated with relative rest followed by physical therapy. Important elements of treatment typically include strengthening the rotator cuff and scapular stabilizers and stretching the posterior shoulder capsule. (See "Rotator cuff tendinopathy", section on 'Treatments'.)

Surgical referral should be obtained expeditiously for acute full-thickness tears associated with weakness and for cases where the patient fails to improve with physical therapy. Significant retraction identified by diagnostic imaging also indicates a need for surgical referral. Physical therapy for patients with rotator cuff injuries but no surgical indications and the management of rotator cuff tears are discussed in detail separately. (See "Rehabilitation principles and practice for shoulder impingement and related problems" and "Management of rotator cuff tears".)

Subacromial glucocorticoid injections have been used to reduce symptoms acutely [1]. After such injections, the athlete must refrain from throwing for five days [2]. However, the use of glucocorticoid injections to treat musculotendinous injury remains controversial. (See "Overview of the management of overuse (persistent) tendinopathy", section on 'Glucocorticoids'.)

Labral tears — Treatment of labral tears may be nonoperative with physical therapy, including strengthening of the rotator cuff, biceps, and scapular stabilizers, and stretching of the posterior shoulder capsule. However, many throwing athletes ultimately need surgical debridement or repair in order to return to sport. (See "Superior labrum anterior to posterior (SLAP) tears", section on 'Management'.)

Glenohumeral internal rotation deficiency — Patients with glenohumeral internal rotation deficiency (GIRD) are managed nonoperatively. Surgery should be reserved for the rare symptomatic patient who does not respond to nonoperative treatment [3]. Nonoperative treatment consists of rest from throwing, stretching the posterior shoulder capsule and pectoralis minor muscle, strengthening the posterior shoulder musculature (especially the subscapularis and serratus anterior), and glenohumeral joint mobilization. Useful stretches include the sleeper stretch and the cross-body adduction stretch (figure 1). (See "Throwing injuries of the upper extremity: Clinical presentation and diagnostic approach", section on 'Shoulder injuries' and 'Stretching exercises' below and 'Strength, balance, and plyometric exercises for throwers' below.)

SICK scapula syndrome and scapular dyskinesis — Treatment of scapular dyskinesis and scapular malposition, inferior medial border prominence, coracoid pain and malposition, and dyskinesis (SICK scapular syndrome) begins with relative rest by limiting throwing. Treatment to address underlying dysfunction includes stretching of the pectoralis minor muscle and posteroinferior shoulder capsule as well as strengthening of the rotator cuff and scapular stabilizing muscles. (See "Rehabilitation principles and practice for shoulder impingement and related problems", section on 'Rehabilitation program' and "Throwing injuries of the upper extremity: Clinical presentation and diagnostic approach", section on 'Shoulder injuries'.)

Proximal humeral epiphysiolysis ("Little League shoulder") — Little League shoulder is treated with rest and activity modification. Typically, symptoms resolve with two to three months of relative rest. During this period, clinicians should educate the patient, the parents/caregivers, and (ideally) the coaches about appropriate rest between pitching episodes; the Pitch Smart guidelines and other prevention measures are discussed below. (See 'Prevention' below.)

The patient should participate in a strength program that includes both the core and lower extremities. A stretching program is especially important for athletes with motion limitations consistent with GIRD, as these athletes appear to be at increased risk for recurrence [4]. Prior to resuming pitching, the athlete should complete a return-to-throwing program. Often, a review of the athlete's biomechanics is useful, as many young throwers have a tendency to throw using primarily their arm and shoulder rather than generating power with their lower body. (See 'Follow-up care and return-to-throwing program' below and 'Exercise and throwing programs for treatment and injury prevention' below and "Throwing injuries of the upper extremity: Clinical presentation and diagnostic approach", section on 'Shoulder injuries'.)

Transient subluxation ("dead arm syndrome") — Management of dead arm syndrome primarily involves treatment of the underlying pathology. Patients with isolated rotator cuff pathology often respond well to physical therapy, including strengthening of the rotator cuff. Such exercises are described below. (See 'Upper extremity strength exercises' below.)

Throwers with labral pathology often require surgical treatment [3,5]. (See "Superior labrum anterior to posterior (SLAP) tears", section on 'Management' and "Throwing injuries of the upper extremity: Clinical presentation and diagnostic approach", section on 'Shoulder injuries'.)

Bennett lesion — A Bennett lesion is a mineralization that develops at the posteroinferior glenoid in throwing athletes. Bennett lesions are often asymptomatic, and treatment is controversial. Some surgeons excise such lesions while others concentrate on correcting strength or biomechanical deficits around the shoulder. There is little published evidence to guide decision-making, and no study has compared operative and nonoperative treatment. In one surgical case series, 11 of 16 patients returned to baseball following arthroscopic resection [6]. While Bennett lesions are often asymptomatic, their presence suggests chronic loading of the posterior capsule. Thus, while athletes who are asymptomatic do not need to stop throwing, it would behoove them to start a prevention program similar to the one used to manage GIRD to protect the shoulder complex. (See "Throwing injuries of the upper extremity: Clinical presentation and diagnostic approach", section on 'Shoulder injuries'.)

Elbow conditions

Ulnar collateral ligament sprain — Partial ulnar collateral ligament (UCL) tears are generally treated with six weeks of relative rest and physical therapy with an emphasis on strengthening the common flexor muscles [2,7,8]. Although non-throwing athletes rarely require surgery for complete UCL tears, throwing athletes typically do and should be referred to an orthopedic surgeon with experience managing such injuries. (See "Throwing injuries of the upper extremity: Clinical presentation and diagnostic approach", section on 'Elbow injuries'.)

Valgus extension overload syndrome — Treatment of valgus extension overload (VEO) syndrome begins with relative rest for two to six weeks followed by a return-to-throwing program. Patients who do not improve despite compliance with an appropriate nonoperative treatment program may be candidates for arthroscopic debridement and are referred to a knowledgeable orthopedic surgeon. (See 'Follow-up care and return-to-throwing program' below and "Throwing injuries of the upper extremity: Clinical presentation and diagnostic approach", section on 'Elbow injuries'.)

"Little League elbow" — Treatment of Little League elbow involves no throwing for at least four to six weeks. During this period, clinicians should educate the patient, the parents/caregivers, and (ideally) the coaches about appropriate rest between pitching episodes; the Pitch Smart guidelines and other prevention measures are discussed below. (See 'Prevention' below.)

The patient should participate in a strength program that includes both the core and lower extremities. Prior to resuming pitching, the athlete should complete a return-to-throwing program. Often, a review of the athlete's biomechanics is useful, as many young throwers have a tendency to throw using primarily their arm and shoulder rather than generating power with their lower body. (See "Throwing injuries of the upper extremity: Clinical presentation and diagnostic approach", section on 'Elbow injuries' and 'Exercise and throwing programs for treatment and injury prevention' below and 'Follow-up care and return-to-throwing program' below.)

Olecranon stress fracture — Treatment of an olecranon stress fracture begins with relative rest for up to six months followed by a return-to-throwing program. Patients who do not improve despite compliance with an appropriate nonoperative treatment program or who must return quickly to throwing may be candidates for surgical fixation [9]. (See "Throwing injuries of the upper extremity: Clinical presentation and diagnostic approach", section on 'Elbow injuries' and 'Follow-up care and return-to-throwing program' below.)

Ulnar neuropathy — The primary nonoperative treatment of ulnar neuropathy in throwers is rest until asymptomatic, in conjunction with a physical therapy rehabilitation program [10-12]. For symptomatic relief, acute exacerbations of ulnar neuropathy may be treated with analgesics, such as antiinflammatory medications. Other medications are not typically used.  

Local injection of a glucocorticoid is no longer routinely done. However, small randomized trials report that it may provide short-term relief and thus may be considered in select cases (eg, player near retirement who only has symptoms while throwing) [13-15]. For permanent relief, cessation of the inciting activity or surgical release or transfer of the nerve may be needed. (See "Ulnar neuropathy at the elbow and wrist", section on 'Management'.)

Osteochondral defect — Stable osteochondral defects with intact cartilage can usually be treated with two to three months of absolute rest from throwing. Unstable lesions with disruption of the overlying cartilage usually require excision or repair. Loose bodies generally require surgical excision. (See "Throwing injuries of the upper extremity: Clinical presentation and diagnostic approach", section on 'Elbow injuries'.)

Effort thrombosis/Paget-Schroetter syndrome — The diagnosis and treatment of effort thrombosis is reviewed in detail separately. (See "Primary (spontaneous) upper extremity deep vein thrombosis".)

Trunk and lower extremity conditions — Clinicians should be aware that throwing athletes are at risk for back, trunk, hip, and lower extremity injuries, as effective throwing requires that the force generated in the lower extremities be transferred to the upper extremity. Possible injuries include low back muscle strain, spondylolysis, oblique muscle strain, hip labral tears, and hamstring injuries. In addition to the primary injury, trunk and lower extremity deficits may predispose throwers to upper extremity injury. As part of their management, clinicians should evaluate for trunk and lower extremity injuries (including history, motion restrictions, and neuromuscular control) and include appropriate corrective exercises as indicated. (See "Spondylolysis and spondylolisthesis in child and adolescent athletes: Clinical presentation, imaging, and diagnosis" and "Hamstring muscle and tendon injuries".)

According to a systematic review of 14 studies, decreased hip internal rotation, altered foot arch position, and decreased lower extremity balance and neuromuscular control were associated with an increased risk of elbow injuries among baseball players [16]. A small cohort study of professional baseball pitchers reported that those with decreased lumbopelvic control had a higher incidence of upper extremity injury [17].

FOLLOW-UP CARE AND RETURN-TO-THROWING PROGRAM — Physical therapy to address both injuries and dysfunction that may have predisposed to injury is the mainstay of treatment for many upper extremity, throwing-related conditions. Prior to embarking upon a rehabilitation program, an assessment of the athlete should be performed to identify possible sources of dysfunction.

An appropriate physical therapy program includes progressive mobility and strength exercises of uninjured structures (eg, lower extremity and trunk) based on identified needs. Gradually, exercises involving the injured extremity are introduced as symptoms abate and the primary injury heals. This is followed by the addition of a plyometric program that involves exercises such as throwing a weighted ball against a trampoline or with a partner to develop proprioception and strength. When the athlete manifests no tenderness, no pain to resisted motion or passive stretch, and no pain during or after performance of plyometric exercises, a progressive throwing program may be initiated. The exercises programs used in rehabilitation are discussed below. (See 'Exercise programs for rehabilitation and injury prevention in throwers' below and 'Stretching exercises' below and 'Strength, balance, and plyometric exercises for throwers' below.)

Throwing programs for rehabilitation and injury prevention vary greatly, and such components as maximum throwing distance, number of throws, and intensity of throwing are the source of ongoing debate. Biomechanical studies show that throwing mechanics and the stresses placed on the elbow and shoulder change as distance increases [2,18]. At 120 feet (37 meters), players no longer throw with a "downhill" trajectory, and mechanics begin to change. At 180 feet (55 meters), shoulder and elbow stresses begin to rise to potentially dangerous levels. Based on this data, we generally recommend that pitchers gradually move to a maximum distance of 120 feet (37 meters) and position players to a maximum 150 to 180 feet (46 to 55 meters) in long toss programs. A sample progressive throwing program for throwers who have recovered from an injury or are returning to sport after a layoff (eg, season playing a non-throwing sport) and are working towards a return to play is provided in the following table (table 1).

COMPLICATIONS

Musculoskeletal injury — In general, complications from throwing injuries primarily relate to the inability to return successfully to throwing activity and to early degenerative changes, in particular shoulder and elbow osteoarthritis.

Effort thrombosis/Paget-Schroetter syndrome — Complications of thrombosis include post-thrombotic syndrome, which is characterized by persistent pain, heaviness of the limb, and chronic swelling [19].

RETURN TO SPORT OR WORK — In general, an athlete may return to throwing when they are asymptomatic, have regained full strength, and have successfully completed a well-designed return-to-throwing program. The athlete may return to sport sooner if they can be moved to a position that does not require significant throwing (eg, first base or designated hitter in baseball).

PREVENTION — Many throwing injuries are related to overuse, high velocity, and poor mechanics [20-23]. Other risk factors for shoulder and elbow injuries include older age, greater height, participation on multiple teams, throwing with arm fatigue, and possibly mound height. Strategies for preventing throwing-related injuries of the upper extremity include avoiding overuse, correcting mechanical flaws, increasing strength, maintaining mobility, and completing proper warm-up and cool-down exercises.

Studies suggest that limiting the number of pitches thrown and the percentage of the year that an athlete is involved in throwing sports may decrease injury risk [24-27]. USA Baseball and Major League Baseball have promoted recommendations for limiting pitching volumes and types based on these and other studies, which can be found at the website in the following reference [28].

Clinicians should be aware that baseball pitch counts often underestimate an athlete's actual throwing volume, as warm-up pitches and bullpen activity may not be recorded and may increase throwing volume by more than 40 percent [29]. Young athletes often play multiple positions throughout a season. Thus, total throwing volume can be up to 10 times greater than pitch count totals [30]. In addition, youth softball typically has no pitch count limits, and softball pitchers frequently throw in consecutive games during tournaments. An observational study of 14 youth softball pitchers reported that incomplete recovery following pitching consecutive games during a tournament produced a progressive loss of strength, increased fatigue, and shoulder pain, which are factors associated with an increased risk of injury [31].

In addition to workload, increased throwing velocity is a risk factor for elbow and shoulder injuries at both the youth and professional levels [20-23,32]. Furthermore, athletes who mature relatively early and are able to throw harder are often asked to pitch at a younger age, recruited to play on multiple teams, and sometimes pressured into specializing in baseball [20]. In an observational study of 746 major league baseball players over eight years, early sports specialization was associated with an increased risk of overuse, upper extremity injury, and decreased career longevity compared with participation in multiple sports during high school [33].

A number of biomechanical risk factors for elbow and shoulder injuries have been identified [3,34]. By using motion analysis to evaluate a pitcher's throwing motions, clinicians can determine whether such factors are present and recommend modifications that may decrease the risk of injury. However, some pitchers may find that suggested changes in biomechanics cause changes in ball motion or velocity that reduce their effectiveness. Some of the more common biomechanical throwing errors that can place undue stress on the shoulder and elbow include:

●Hooking the ball (early shoulder and elbow extension with wrist flexion) during arm cocking phase (picture 1)

●Low shoulder abduction (dropped elbow) at time of foot contact (picture 2)

●Excessive horizontal shoulder abduction at foot contact and through early acceleration (picture 3)

●Premature trunk rotation during initiation of acceleration (picture 4)

●Excessive elbow flexion at foot contact, moving to excessive elbow extension at ball release (picture 5)

●Inadequate follow-through (picture 6)

While these flaws can often be spotted by trained professionals in "real time," video analysis often involving slow motion replay is necessary for a thorough assessment of throwing biomechanics.

In addition to avoiding overuse and biomechanical flaws, exercise programs designed to improve strength and maintain mobility are important for preventing throwing-related upper extremity injuries. While the importance of shoulder and arm strength is obvious to most throwing athletes, the importance of strong scapular stabilizers, trunk, and lower extremity muscles may not be. Thus, it is important to educate throwing athletes about the importance of these muscles and to provide appropriate strength and conditioning programs.

Most scapular and rotator cuff exercise programs for pitchers are modeled on the "Thrower's 10 Program" designed by James Andrews, MD and physical therapists Kevin Wilk and Michael Reinhold [35-37]. This program is designed to be one part of a year-round program of strength and mobility that targets the main muscles involved in throwing. An Advanced Thrower's 10 Program published in 2011 builds upon the original with the goal of coordinating the upper extremity with the core and lower extremity. This program incorporates exercises to develop single-leg balance, trunk and abdominal strength, and ipsilateral musculature.

Suggested exercise programs for throwers, including descriptions of the specific exercises used in these programs, are described below. Continual work to prevent dysfunction in the shoulder capsule remains an important element of all programs. According to a 2018 systematic review of studies of exercises for overhead athletes with shoulder conditions, evidence is generally of low quality, but the best available evidence supports the use of single-plane, open-chain upper extremity exercises and closed-chain upper extremity exercises, similar to those included in our recommendations below [38]. (See 'Exercise programs for rehabilitation and injury prevention in throwers' below and 'Strength, balance, and plyometric exercises for throwers' below and 'Stretching exercises' below.).

The idiosyncratic biomechanical demands of pitching require specific adaptations that must be accounted for when designing training programs for throwers. As an example, while the ratio of shoulder internal rotation to external rotation is generally 3:2 in normal individuals and in many overhead athletes, healthy pitchers may reach a 4:3 ratio while developing a "posterior dominant" shoulder (ie, one with greater external rotation) that may be more resistant to injury. Thus, strength exercises for the shoulder should be performed in a controlled manner and include some emphasis on the eccentric movement in order to mimic the demands of deceleration that occur following release of the ball when pitching.

EXERCISE AND THROWING PROGRAMS FOR TREATMENT AND INJURY PREVENTION

Key principles for training and rehabilitation programs — Sample programs that may be used for treating throwing-related injuries of the upper extremity or for preventing such injuries are illustrated in the following section and in the accompanying tables [35-37,39,40]. Other effective programs are available, but the programs provided are all reasonable approaches for their stated purpose. Programs for in-season throwing, off-season throwing, strength, proprioception, core strengthening, and plyometric training are included.

The following principles should be kept in mind when selecting an exercise or rehabilitation program for a thrower:

●The athlete should warm up thoroughly prior to every training session and should maintain cardiovascular fitness throughout any throwing-related training program.

●A program should be selected that is appropriate for any upper extremity injury or identified dysfunction.

●Progression to the next stage of any program should never be undertaken until the thrower can perform the exercises of the current stage properly and without undue discomfort; progression through a program should be gradual.

●Programs for the shoulder should include strength exercises for rotator cuff and scapular stabilizing muscle groups and mobility exercises for the glenohumeral joint.

●Trunk, abdominal, and lower extremity strengthening, as well as proprioceptive training in both the upper and lower extremities, are important elements of any effective program.

●Appropriate resistance should be used for all strength exercises.

It is appropriate to begin exercises using weights ranging from 1 to 3 lbs (0.5 to 1.5 kg) and to increase the weight when three sets of 20 repetitions can be performed without difficulty. Ideally, the resistance used should become challenging when the athlete reaches between 10 and 20 repetitions.

Reasonable resistance goals for shoulder and elbow exercises in the Thrower's 10 and comparable training programs are the following:

•High school pitchers: 5 lbs (2 kg) for shoulder; 15 lbs (7 kg) for elbow and forearm

•College pitchers (ages 18 to 23): 7 lbs (3 kg) for shoulder; 20 to 25 lbs (9 to 11 kg) for elbow and forearm

•Professional pitchers: 8 to 10 lbs (3.5 to 4.5 kg) for shoulder; 25 to 35 lbs (11 to 16 kg) for elbow and forearm

●Once satisfactory strength and motion have been achieved, sport-specific progressions should include upper extremity plyometric exercises that mimic the demands of throwing. Medicine ball programs focusing on the posterior chain of the shoulder and on linking hip and trunk movements with the upper extremity are used for both rehabilitation and to help throwers regain velocity.

●Throwing weighted balls is a hybrid exercise that combines elements of throwing and resistance training [41]. Although such exercises may produce increases in throwing velocity, they are associated with a substantial risk of injury and should be avoided [42].

Exercise programs for rehabilitation and injury prevention in throwers

Program guidelines — Several strength and rehabilitation programs for throwers are included in this section. For each program, we recommend that the athlete perform the routine three days per week and not on consecutive days. For throwers performing exercises as part of their rehabilitation, pain should be kept to a minimum (below 2 to 3 on a scale of 1 to 10), and fatigue should not be excessive (roughly 6 on a scale of 1 to 10).

The targeted number of sets and repetitions for each strength and plyometric exercise, except where otherwise noted (eg, exercises performed for time rather than repetitions), is as follows:

●Weeks 1 to 2: Three sets of 10 repetitions

●Weeks 3 to 4: Three sets of 15 repetitions

●Weeks 5 to 6: Three sets of 20 repetitions

●Approximately 30 seconds to one minute of rest is taken between sets

Basic program — The following is a basic strength program suitable for high school pitchers and other young throwers who are recovering from an injury or working to improve their performance and reduce their risk of injury. The participant should complete an appropriate, light warm-up (eg, five minutes on stationary bicycle or treadmill) prior to performing the strength exercises. In addition to the strength exercises, posterior shoulder capsule stretches should be performed regularly by every thrower. The program should be supervised by a knowledgeable coach or clinician. Descriptions of how to perform the specific exercises included are provided below. (See 'Strength, balance, and plyometric exercises for throwers' below and 'Stretching exercises' below.)

●Upper extremity strength exercises:

•Shoulder abduction to 90 degrees (movie 1)

•Side-lying shoulder external rotation (picture 7)

•Prone horizontal abduction (picture 8)

•Prone rowing (picture 9)

•Prone rowing into external rotation (picture 10)

●Core strength exercises:

•Plank (picture 11 and picture 12)

•Side planks (picture 12)

•Bridges with leg extension (picture 13)

•Press-ups (picture 14)

•Push-ups (picture 15)

•Single leg deadlift with minimal knee bend (ie, Romanian deadlift) (picture 16)

Advanced program — The following is an advanced strength program suitable for college and professional pitchers and other elite throwers who are recovering from an injury or working to improve their performance and reduce their risk of injury. The participant should complete an appropriate, light warm-up (eg, five minutes on stationary bicycle or treadmill) prior to performing the strength exercises. In addition to the strength exercises, posterior shoulder capsule stretches should be performed regularly by every thrower. The program should be supervised by a knowledgeable coach or clinician. Descriptions of how to perform the specific exercises are provided further below. (See 'Strength, balance, and plyometric exercises for throwers' below and 'Stretching exercises' below.)

●Upper extremity strength exercises:

•Shoulder abduction to 90 degrees (movie 1)

•Side-lying external rotation (picture 7)

•Prone horizontal abduction (picture 8)

•Prone rowing (picture 9)

•Prone rowing into external rotation (picture 10)

•Scaption with external rotation (picture 17)

•Elbow flexion (picture 18)

•Elbow extension (picture 19)

•Wrist flexion (picture 20)

•Wrist extension (picture 21)

•Supermans (picture 22)

•Forearm pronation (picture 23)

•Forearm supination (picture 24)

●Lower extremity and core strength exercises:

•Plank (picture 11 and picture 12)

•Side planks (picture 12)

•Bridges with leg extension (picture 13)

•Press-ups (picture 14)

•Push-ups (picture 15)

•Draw-in with leg extension (picture 25)

•Square-steps (picture 26)

•Single-leg Romanian deadlift (picture 16)

•Single-leg balance with hip abduction against resistance (picture 27 and movie 2)

•Lunges (movie 3)

●Plyometric exercises

•External rotation from side using tubing resistance (picture 28 and movie 4)

•External rotation with abducted shoulder using tubing resistance (movie 5)

•Overhead medicine ball (Plyoball) throws (movie 6)

•External rotation (Plyoball) throws (movie 7)

•Kneeling deceleration baseball throws (picture 29 and movie 8)

•Kneeling baseball throws (picture 30 and movie 9)

•Chest pass (movie 10)

•Hitter's push (picture 31 and movie 11)

•Diagonal wood chop (picture 32 and movie 12)

Basic exercise program for throwers without access to expert supervision — As a rule, we strongly prefer that throwers who are recovering from injury or participating in a strength and injury-prevention program perform their exercises under the supervision of a knowledgeable clinician or coach who can correct their technique and gauge their progress. However, not all young throwers have access to expert supervision. For such throwers, the following basic exercise program may be used (table 2). The key principles described above apply to all throwers participating in such a program. (See 'Key principles for training and rehabilitation programs' above.)

Stretching exercises

Posterior shoulder capsule stretching program — Maintaining full posterior shoulder capsule flexibility is crucial for avoiding injury in throwers. Stiffness of the posterior capsule limits glenohumeral motion and can make the shoulder susceptible to injury. Decreased internal rotation at 90 degrees of abduction has been found to increase the risk for elbow ulnar collateral ligament (UCL) tears.

The following table provides a basic stretching program for the posterior capsule (figure 1). The included stretches should be maintained at low intensity but for long duration, and they should be pain free. Success with this program is gained through frequency, not intensity, of stretching. Therefore, at a minimum, the athlete should perform two to three stretches for 30 seconds each, repeating this during three to four sessions over the course of the day.

Chest and forearm stretching program — A basic static stretching program for throwers consists of the stretches used for the posterior capsule (figure 1) and a few additional exercises primarily for the chest and forearms.

The chest stretches consist of two exercises, one performed while lying supine on a foam roller and the other performed in the corner of a room. Each is performed for three sets of 30-second holds. When performing the W stretch on the foam roller, make sure the foam roller is aligned in the center of the back under the spine. Place the arms in the 90/90 position shown in the photograph, relax, and allow the elbows to drop towards the floor (picture 33). When performing the corner W stretch, stand about 3 feet (1 meter) from the corner of a room with one forearm on each wall at shoulder height and the elbows flexed to 90 degrees. Then relax and gradually lean into the corner.

To stretch the wrist flexors (volar forearm muscles), straighten the elbow of the throwing arm with the palm facing up and then use the other hand to extend the wrist, thereby pushing the hand and fingers towards the ground (picture 34). To stretch the wrist extensors (dorsal forearm muscles), straighten the elbow of the throwing arm but now with the palm facing down, and then use the other hand to flex the wrist, thereby pushing the hand and fingers towards the ground (picture 35).

Lower extremity and trunk stretching program — Lower extremity and trunk mobility deficits can interrupt kinetic chain connections and increase strain on the shoulder and elbow. All stretches are held for 30 to 60 seconds and repeated twice.

●Hip flexor stretch – Start in a split stance with the target leg in extension and the contralateral leg placed forward and in flexion. Tighten the abdominal muscles while shifting your weight forward until a stretch is felt in the anterior thigh of the rear leg (figure 2).

●Hamstring stretch – Place the heel of the target leg on a step or chair. While maintaining a neutral spine (ie, low back is kept straight), bend forward at the hips until a stretch is felt in the posterior mid-thigh (picture 36).

●Ankle plantar flexor (calf) stretch – Facing a wall, assume a split stance with the target leg back in extension. Keeping the foot pointed straight ahead and maintaining heel contact with the ground, shift your weight forward until a stretch is felt in the posterior calf (picture 37).

●Hip internal rotation stretch – Stands with your feet shoulder-width apart while holding a dowel rod in both hands with shoulders flexed forward to 90 degrees (arms parallel to ground). Gradually pivot the contralateral leg around toward the target side, thereby creating a closed-chain hip internal rotation stretch (picture 38).

●Hip external rotation stretch – Assume a supine position on the ground with both knees flexed. Place the outer ankle of the target leg on the distal thigh of the contralateral leg (picture 39). Wrap both hands around the posterior thigh of the contralateral leg and pull that leg into hip flexion until a stretch is felt in the posterior hip of the target leg.

●Trunk rotation stretch – Begin in a side-lying position on the ground with hips and knees flexed to 90 degrees and both shoulders flexed to 90 degrees. While maintaining the lower extremity and bottom arm positions, lift and rotate the top arm and trunk into an open-chest position, creating a stretch through the chest (picture 40). Switch sides and repeat in the opposite direction.

Strength, balance, and plyometric exercises for throwers

Upper extremity strength exercises — The exercises described below are based on a program originally developed by experienced clinicians to help throwers develop strength in their rotator cuff, scapular stabilizer, and wrist flexor and extensor muscles [35-37]. We have modified the original program slightly to accommodate throwers who might not have access to particular equipment and to avoid potential problems posed by unsupervised exercises with elastic bands. The exercises below are used widely and based on sound biomechanical principles, but there are few rigorous controlled outcome studies of such programs.

●Shoulder abduction to 90 degrees – The thrower stands with their arm at their side, elbow straight, and palm against their lateral thigh. The thrower raises their arm laterally, keeping the palm down, until it reaches 90 degrees of lateral shoulder abduction (shoulder height) and then returns it to the starting position (picture 41).

●Scaption with external rotation – The thrower stands with their elbow straight and thumb up (ie, extended like a hitchhiker) and then raises their arm to shoulder level and no further. Movement occurs in the scapular plane, about 30 degrees anterior to the frontal plane. The thrower maintains the arm at shoulder height for two seconds and then slowly lowers it to the starting position (picture 17).

●Side-lying external rotation – The thrower lies on their uninvolved, or non-throwing, side. The throwing arm begins at the side of the body with the elbow bent to 90 degrees. While keeping the elbow of the throwing arm fixed to their side, the thrower externally rotates their shoulder, holds the rotated position for two seconds, and then slowly lowers the arm to the starting position (picture 7).

●Prone horizontal abduction (neutral) – The thrower begins the exercise lying face down with their throwing arm hanging straight towards the floor. The thrower raises their arm to the side, keeping the palm facing down, until it is parallel to the floor, maintains this position for two seconds, and then slowly lowers their arm back to the starting position (picture 8).

●Prone horizontal abduction (external rotation: 100 degrees shoulder abduction): The thrower begins the exercise lying face down with their throwing arm hanging straight towards the floor and thumb up (ie, extended like a hitchhiker). The thrower raises their arm to the side in a plane slightly superior to the shoulder until the arm is parallel to the floor. This position is held for two seconds and then slowly lowered back to the starting position (picture 42).

●Prone rowing – The thrower begins the exercise lying face down with their throwing arm hanging straight towards the floor, holding an appropriate dumbbell. Using a steady pace, the thrower raises the dumbbell to their chest, holds the position at the top for two seconds, and then gradually lowers the weight back to the starting position (picture 9).

●Prone rowing into external rotation – The thrower begins the exercise lying face down with their throwing arm hanging straight towards the floor, holding an appropriate dumbbell. The thrower gradually raises their arm, while simultaneously bending their elbow, until the arm is at the level of the table and parallel to the floor. The forearm remains pointed towards the floor. After pausing for one second in this position, the thrower externally rotates their shoulder until the dumbbell is as the height of the table while maintaining elbow flexion at 90 degrees. This position is held for two seconds, then the shoulder is gradually internally rotated, and the arm lowered back to the starting position (picture 10).

●Press-ups – While seated, the thrower firmly grasps both sides of the chair or table with their palms down. The hands should be directly below the shoulders. The thrower then slowly pushes downward through their hands to elevate their body off the chair or table, holds the elevated position for two seconds, and slowly lowers their body back to the starting position (picture 14).

●Push-ups – The thrower assumes a standard push-up position, with their hands below the level of their shoulders (ie, caudad) and no more than shoulder width apart. The thrower pushes up as high as possible, rolling shoulders forward (maximal scapular protraction) after their elbows are straight (picture 15). If a standard push-up is too difficult or causes pain in the shoulder or elbow, the thrower may start with push-ups against a wall and then gradually perform the exercise on increasingly lower surfaces (eg, chair, step), until it can be performed on the floor (picture 43).

●Elbow flexion and extension

•Elbow flexion – From a standing position with their arm against their side and palm facing inward while holding an appropriate dumbbell, the thrower flexes their elbow while gradually turning the palm upward. The top position is held for two seconds, and then the arm is lowered back to the starting position (picture 18).

•Elbow extension (with abduction) – From a standing position, the thrower holds an appropriate dumbbell, raises their throwing arm overhead, and flexes their elbow so it points directly upward. The opposite hand supports the elbow. The thrower then extends their elbow until the arm is straight overhead. The top position is held for two seconds, and then the arm is lowered back to the starting position (picture 19).

●Wrist flexion and extension

•Wrist extension – While holding an appropriate dumbbell with their palm facing downward, the thrower extends their wrist as far as possible, holds the position for two seconds, and then slowly lowers it to the starting position (picture 21).

•Wrist flexion – While holding an appropriate dumbbell with their palm facing upward, the thrower flexes their wrist as much as possible, holds the position for two seconds, and then slowly lowers it to the starting position (picture 20).

●Forearm pronation and supination

•Forearm pronation – While holding one end of an appropriate dumbbell with the grasping thumb pointing up, the thrower rotates the forearm in a controlled fashion back and forth between the thumb-up and palm-down positions (picture 23).

•Forearm supination – While holding one end of an appropriate dumbbell with the grasping thumb pointing up, the thrower rotates the forearm in a controlled fashion back and forth between the thumb-up and palm-up positions (picture 24).

Core strength and balance exercises — A strong torso allows for the efficient transfer of force from the lower extremity to the throwing arm and is therefore important for throwing athletes. We recommend that throwers perform core strengthening exercises two days per week and not on consecutive days. The following are suitable and commonly prescribed exercises:

●Planks – The thrower begins in a push-up position but supporting themselves on their forearms rather than hands and then tightens their abdominal muscles while maintaining a neutral position with their lumbar spine (ie, no rounding and no hyperextension) (picture 11 and picture 12). Initially, the position is held for 30 seconds. Three sets are performed. As the exercise becomes easier, time intervals are increased by 10 to 15 seconds, with a goal of 90 seconds.

●Side planks – The thrower lies on their side braced by their left forearm and then tightens their abdominal muscles while maintaining a neutral position with their lumbar spine (picture 12). Initially, the position is held for 30 seconds. Three sets are performed. As the exercise becomes easier, time intervals are increased by 10 to 15 seconds, with a goal of 90 seconds.

●Bridge with leg extensions – The thrower lies on their back with knees bent and feet flat on the floor. The thrower then lifts their buttocks off the floor (bridge) by moving at the hips. Maintaining this position, the thrower raises one leg and extends their knee until the leg is straight, while keeping the abdominal muscles tight, and then flexes the knee and returns the foot to the floor. The thrower then performs the same maneuver using the opposite leg. Start with 10 repetitions per leg, and perform three sets (picture 13).

●Draw-in with leg extensions – The thrower lays supine with their hips and knees flexed to 90 degrees. Next, the thrower tightens their abdominal muscles and slowly extends one leg while maintaining the pelvis in a neutral position (ie, not allowing the lumbar spine to fall into lordosis). This position is held for three seconds, and then the leg is returned to the starting position. Start with 10 repetitions per leg, and perform three sets (picture 25).

●Superman – While holding a 2- to 5-lb (1- to 2-kg) dumbbell in each hand, the thrower places their belly on a physio-ball in a prone position. Next, the thrower braces their abdominal muscles and brings their arms to a position of 90 degrees of shoulder abduction and external rotation, with the elbows flexed to 90 degrees, as if they were performing an overhead press. The thrower then presses the dumbbells by fully extending their arms outward, ending in a position resembling Superman's flying position. Return to the initial position by retracing the arm path (picture 22).

●Square steps – With an elastic band (eg, TheraBand) encircling both knees, the thrower stands in a half-squat position with toes pointing forward and a neutral spine. The thrower takes 10 steps to the left, 10 forward, 10 to the right, and 10 backward, making a square, while maintaining continuous tension in the band. Perform three sets of the full square. (picture 26).

●Single-leg Romanian deadlift – The thrower balances on one leg while holding a 5- to 8-lb (2- to 3.5-kg) dumbbell in the opposite hand, tightens their abdominal muscles, and slightly flexes their knee. Next, while maintaining a neutral spine, the thrower bends at the hip in order to bring the weight down to the planted foot and then returns to the starting position (picture 16).

●Single-leg balance with hip abduction against resistance – Place an elastic band (eg, TheraBand) around the proximal knees or a single ankle weight around the distal thigh above the knee. The thrower balances on one leg with the knee slightly flexed while tightening their abdominal muscles and then abducts the hip against resistance (from band or weight) (picture 27 and movie 2). While maintaining balance, the player holds this position for the assigned period and then returns to the starting position.

●Lunges – Stand with the feet hip-width apart, keeping the back straight, shoulders back, and abdominal muscles tight. From this position, the thrower steps forward with one leg, landing softly, and allows their knee to bend to around 60 degrees (movie 13). The thrower then pushes back up to the starting point and repeats the movement with the other leg. Continue alternating between legs until the assigned number of repetitions is completed.

Plyometric exercises (Ballistic Six) — The following plyometric exercises are used to develop strength and power in throwers while incorporating the entire throwing range of motion [39,40,43]. For advanced throwers, we recommend performing these exercises two days per week but not on consecutive days and not after performing standard exercises, a throwing program, or other strenuous exercise. Plyometric exercises should be supervised by a knowledgeable coach or clinician. The exercises should be completed without pain and achieve moderate fatigue (roughly a 5 on a scale of 1 to 10).

Suitable resistance should be used, as follows:

●Moderate-resistance elastic band (eg, red TheraBand) for tubing exercises

●2-lb (1-kg) rubber medicine ball (eg, Plyoball) for single-arm exercises

●6-lb (2.7-kg) rubber medicine ball for double-arm exercises

The targeted number of sets and repetitions for each plyometric exercise is as follows:

●Weeks 1 to 2: Three sets of 10 repetitions

●Weeks 3 to 4: Three sets of 15 repetitions

●Weeks 5 to 6: Three sets of 20 repetitions

●Approximately 30 seconds to one minute of rest is taken between sets

Each exercise should be performed quickly in a ballistic manner, keeping the transition from deceleration to throw (amortization phase) as brief as possible to maximize the training effects of the plyometric activity. These exercises should not cause pain and should be stopped if they do so.

Exercises include the following:

●External rotation from side using tubing resistance (movie 4) – With their elbow against their side and hand against their abdomen, the thrower grips elastic tubing attached at about waist height to a fixed object. The thrower stands perpendicular to the attachment point. With moderate to fast speed, the thrower externally rotates their shoulder to approximately 30 degrees past neutral then gradually allows the band to pull the hand back to the starting position (picture 28).

●External rotation with abducted shoulder using tubing resistance (movie 5) – The thrower begins exercise with the arm abducted to 90 degrees and elbow bent to 90 degrees while holding elastic tubing attached to a fixed object at about waist height. The thrower stands facing this object. With moderate to fast speed, the thrower externally rotates their shoulder to 90 degrees of external rotation then gradually allows the band to pull the hand back to the starting position (picture 44).

●Overhead medicine ball throw (soccer throw) (movie 6) – Holding a rubber medicine ball (Plyoball) with two hands overhead, the thrower performs a series of short, quick throws against a wall or to a partner.

●External rotation throw (movie 7) – The thrower stands with shoulder flexed to 90 degrees and elbow bent to 90 degrees holding a small Plyoball. The thrower then externally rotates their shoulder rapidly, throwing the Plyoball to a partner or against a wall. The partner throws the ball back and the thrower catches the ball as it crosses their body, decelerating their arm and returning it to the starting position, and then quickly repeating the motion (picture 45).

●Kneeling deceleration baseball throw (movie 8) – The thrower begins in a half-kneeling position, with their shoulder abducted to 90 degrees and externally rotated to 90 degrees, and facing away from their partner. Their partner throws a Plyoball over the thrower's shoulder and into the path of the throwing arm. The thrower catches the ball and decelerates their arm through the entire path of the deceleration phase, and then quickly reverses their arm motion along the same path and throws the ball back to their partner (picture 29).

●Kneeling baseball throw (movie 9) – A partner throws a small Plyoball to the thrower, who is in a standing or half-kneeling position, facing the partner. With their shoulder at 90 degrees of abduction and 90 degrees of external rotation, the thrower catches the ball, decelerates their arm, and returns it to the starting position. The thrower then throws the Plyoball back to their partner using sound mechanics (picture 30).

The following three exercises are used in addition to the traditional Ballistic Six:

●Chest pass – The thrower holds a small medicine ball with two hands, held at chest height while standing with feet around shoulder-width apart and knees slightly bent. With the abdominal muscles activated, the thrower completes a chest pass to a partner or against a wall (movie 10). The ball is returned and the motion repeated.

●Hitter's push – The thrower stands in a batting stance holding a small medicine ball in front of the trail shoulder (picture 31). The trail hand is to the side of the ball; the lead hand is underneath the ball. The thrower rotates the trunk forcefully and pushes the ball forward towards a partner or wall (movie 11). The ball is returned and the motion repeated.

●Diagonal wood chop – The thrower stands in a batting stance holding a small medicine ball at about shoulder height or a little higher in front of the trailing (or rear) shoulder (picture 32). The thrower rotates the trunk forcefully and thrusts the ball in a downward diagonal direction towards a partner or wall (movie 12). The ball is returned and the motion repeated.

Throwing programs — In addition to performing strength and conditioning exercises, throwers must throw to develop sport-specific endurance, strength, and technique. Below are sample programs suitable for athletes who are returning to throwing after a layoff due to injury or participation in a non-throwing sport, throwing during their sport season, or throwing during their off season.

Terminology for throwing programs — All throwing programs use a progression of throwing velocities and distances to allow pitchers to improve their endurance and strength gradually. Common terms used to describe the different intensities of throwing include the following:

●Lob toss – Throwing at short distance with minimal effort.

●Soft toss – Throwing with a substantial arc to the ball's trajectory at approximately 50 to 60 percent of maximal effort or velocity.

●Firm toss – Throwing with a slight arc at approximately 80 to 85 percent of maximal effort or velocity.

●On-line throwing – Throwing with virtually no arc at approximately 90 to 95 percent of maximal effort.

●Game-intensity throwing – Throwing with 95 percent effort or greater, as if in a game situation.

Active warm-up program for shoulder, arm, and forearm — A number of approaches are used for warming up throwers prior to competition. Although evidence is limited, and many warm-up programs are based on tradition rather than evidence, a few studies have reported favorable results for warm-ups that included flexibility exercises along with lower extremity, upper extremity, and core activation exercises. Although not performed in baseball players, a well-designed, cluster-randomized trial involving 660 elite team handball players (a population of overhead throwing athletes with a shoulder injury profile similar to baseball pitchers) found that a preparticipation exercise program was effective in reducing shoulder injuries over the course of the seven-month season (average prevalence 17 percent [95% CI 16-19] in the intervention group versus 23 percent [95% CI 21-26] in the control group) [44]. Another research group has reported similar results using a comparable program for Little League baseball players [45,46].

The following figure describes a warm-up program that includes many of the exercises used in the team handball study and Little League injury reduction programs that can be used by any pitcher or throwing athlete prior to competition or intensive throwing (figure 3) [44,45]. Athletes should first perform a light five-minute general cardiovascular warm-up (eg, jogging, stationary cycling) followed by posterior shoulder, chest, and forearm stretches (figure 1 and picture 33 and picture 34 and picture 35) prior to the throwing-specific warm-up.

Active cool-down program for shoulder, arm, and forearm — There are no consensus recommendations for post-throwing care and little high-quality evidence to guide such recommendations. According to an observational study of a convenience sample of 20 professional baseball pitchers, a simple one-minute mobility routine is effective for maintaining shoulder and elbow mobility following intensive throwing [47]. On the basis of these results and our clinical experience, we suggest the following approach to cooling down following intensive throwing (eg, game pitching):

●Perform light cardiovascular activity

●Repeat warm-up exercises (figure 3)

●Perform the "two-out" stretching program (picture 46)

Return-to-throwing program — The progressive throwing program contained in the following table is primarily designed for pitchers and other throwers who have recovered from an injury or are returning to sport after a layoff (eg, season plying a non-throwing sport) and are working towards a return to play (table 1). Gradually, throwing distance and intensity are increased. As distances increase beyond 60 feet (18 meters), a step-through (or "crow-hop") is encouraged to help increase the contributions from the lower extremity and trunk.

In-season throwing programs — In-season throwing programs are designed to help pitchers and other throwers maintain endurance and strength while reducing the risk of injury during the competitive season. In-season programs for throwers are provided in the following table (table 3).

Off-season throwing program — Off-season throwing programs are designed to help pitchers prepare for the beginning of the season. Pitchers usually begin such a program about six weeks prior to the start of organized team practices. A sample program is provided in the accompanying table (table 4).

Off-season throwing sessions begin with approximately five minutes of light jogging or stationary cycling, easy sets of selected shoulder and upper extremity warm-up exercises, and five minutes of easy, lob tossing from 10 to 20 feet (3 to 6 meters) before moving to the first prescribed distance of the day's program.

All prescribed throws should be firm but not overthrown. Over the course of a session, throwers should strive to make more precise on-line throws to the target. If the thrower cannot make firm throws at the set distance, the distance should be shortened. Throwers should not advance to the next distance until they are strong enough to complete their present level.

Pitchers should not throw off a mound until they are able to on-line throw 120 feet for the designated time. Their goal is to be able to throw 25 to 30 pitches or five minutes of batting practice off the mound by the time they report for the start of organized practice. The goal for position players is to on-line throw 120 feet for the designated time without discomfort. If at any time during the off-season program an athlete experiences pain, significant discomfort, or other arm problems, they should contact their coach or trainer.

SUMMARY AND RECOMMENDATIONS

●Management – The initial treatment for most throwing injuries is relative or absolute rest. Immobilization is rarely needed and may be detrimental. The definitive treatments for specific throwing-related upper extremity injuries are described in the text and generally entail either rest followed by a progressive rehabilitation program or surgical repair followed by rehabilitation. (See 'Initial treatment' above and 'Shoulder conditions' above and 'Elbow conditions' above.)

●Prevention – Strategies for preventing throwing-related injuries of the upper extremity include avoiding overuse, correcting mechanical flaws, increasing strength, and maintaining mobility. (See 'Prevention' above.)

●Non-throwing exercises for treatment and prevention – A wide range of exercises are used to develop strength, mobility, power, and endurance in order to prevent or recover from injury and to improve throwing performance. A number of programs incorporating these exercises, and descriptions of how individual exercises are performed, are provided in the text. (See 'Key principles for training and rehabilitation programs' above and 'Exercise programs for rehabilitation and injury prevention in throwers' above.)

●Throwing programs for treatment and prevention – In addition to performing strength and conditioning exercises, throwers must throw to develop sport-specific endurance, strength, and technique. A number of throwing programs to help athletes return to throwing following injury or layoff, or to maintain fitness, are described in the text. (See 'Throwing programs' above.)