CONSERVATIVE MANAGEMENT OF SHOULDER INJURIES 0030-5898/00 $15.00 + .OO

THE PAINFUL SHOULDER IN THE SWIMMING ATHLETE

Marilyn M. Pink, PhD, PT, and James E. Tibone, MD

People swim for fitness, for recreation, or for competition. Swimming is enjoyed by approx- imately 100 million Americans13 of all ages. No specially designed implements are required to swim, and no team or rules are required to en- joy the sport. Nobody invented swimming. The only thing needed to become a swimmer is water.

The shoulder is a vulnerable joint in the swimmer. Ninety percent of the propulsive force in swimming comes from the upper ex- t remi t~ .~ ,~ Most other sports (e.g., running, bi- cycling, golfing, pitching, or batting) require the feet to push into the ground (or bicycle pedal), which initiates the propulsive or ground reaction force. In swimming, there is no such force. In swimming, the athlete must pull the body over the arm.

Another unique aspect of swimming is the factor of upper extremity endurance. Compet- itive athletes may swim 10,000 to 14,000 m(6 to 8 miles) a day, 6 or 7 days a week. Distance swimmers may double that distance. This dis- tance equates to 16,000 shoulder revolutions per week, or approximately 2500 revolutions per day. Many of these revolutions are done in sequence, without any rest for the muscles to recover. Although a golfer swings, then walks, then swings again, a swimmer undergoes con- tinuous revolutions. This continuous move- ment puts stress on the shoulders, leading to injury from repetitive microtrauma.

To add to the complexity of these mechani- cal characteristics of swimming is the fact that the shoulder is relatively unstable. When put- ting together the training distances, unique propulsive demands, and inherent shoulder laxity, the risk of injury is understandably high. Shoulder problems are reported in 66% of swimmers, whereas only 57% of profes- sional pitchers, 44% of collegiate volleyball players, and 29% of collegiate javelin throw- e r ~ * ~ report shoulder injuries.

Given the popularity of swimming and the high risk of injury, many clinicians come into contact with the swimmer's shoulder. This article focuses on conservative treatment for swim- mer's shoulder. To design the optimal treatment, one needs to understand the mechanism of in- jury, diagnostic tools, and subtle signs of in- jury. Because the freestyle stroke is the com- monest stroke in swimming, the focus here is on the freestyle.

MECHANISM OF INJURY

Painful Areas

The earlier that a swimmer reports shoulder pain, the more specific the diagnosis can be. If the swimmer waits to report pain, inflamma- tion has set in, and the pain is more global, masking the inciting symptoms. Global pain

From the Biomechanics Laboratory, Centinela Hospital Medical Center, Inglewood (MMP); the Department of Ortho- paedics, University of Southern California WT); and the Kerlan-Jobe Orthopaedic Clinic (JET), Los Angeles, California

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248 PINK & TIBONE

has led clinicians to make global diagnoses, such as swimmer’s shoulder. Likewise, the treat- ment is then nonspecific with limited success. This limited success is demonstrated by the fact that more than half of shoulder injuries in swimmers recur.3o Also, if a swimmer tries to wait out or swim through the pain, anatomic damage is likely to occur. Conservative treat- ment is much more effective if intervention oc- curs before that point. A valuable message that can be given to coaches and swimmers is that pain is telling them something. Teaching ath- letes and coaches the difference between pain and soreness can help minimize the damage and hasten the return to sport after an injury.

A survey of 233 competitive swimmers on 17 collegiate teams9 asked for the location of pain and the positions during the stroke of the most intense pain. The anterior-superior re- gion of the shoulder was identified in 44% of the swimmers as the area of pain. Diffuse pain was identified in 26% of the swimmers, with lesser frequencies reported for the anterior-in- ferior region of the shoulder (14% of the swim- mers), posterior-superior region (10% of the swimmers), and posterior-inferior region (4% of the swimmers). It is likely that swimmers who identified diffuse pain had not acknowl- edged the pain when it was more localized, and the inciting symptoms were masked by inflammation and more severe damage.

In the freestyle stroke, the first half of pull- through was most frequently identified as the painful phase of the stroke (approximately 70% of symptoms were noted at this time)? Another vulnerable point of the stroke ap- peared during the first half of recovery (18% of symptoms were elicited at these points) (Fig. 1). During the first half of pull-through, the arm is unilaterally pulling the body over the arm. The arm generates the propulsive force. In a separate surveymore than half of the swimmers reported that increasing the in-

tensity of a workout was one of the two factors (the other being an increase in distance) that appeared to provoke shoulder pain.30 The in- creased intensity implies that the magnitude of the propulsive forces would be a factor in shoulder injuries. During the second half of pull-through, it may be that the swimmer with a shoulder injury fails to generate the propul- sion from that arm and is relying on the con- tralateral arm to pull the body forward.

Toward midrecovery, the humerus is hyper- extended and swinging the forearm forward. It has been suggested that at this point the hu- merus moves into maximal external rotation, and this has been equated to the late cocking phase of the baseball pitch. Although it is true that at this point the humerus is as far into external rotation as it goes during the freestyle stroke, it is nowhere near the degree of maxi- mal external rotation required during the base- ball pitch. During the midrecovery phase of the freestyle stroke, the humerus is closer to neutral rotation than it is to maximal exter- nal rotation. This singular fact underscores the issue that the mechanics of injury in the swimmer are unique for that sport-they are unique for each stroke within swimming. A grouping of all overhead athletes does injustice for the specificity of understanding injury me- chanics.

As the freestyle swimmer approaches mid- recovery it is the humeral hyperextension that likely causes the pain. In this position, the hu- meral head is pushed anteriorly. Any anterior impingement, labral damage, or inflammation would be aggravated in this position.

Anatomic Areas of Injury

Based on the knowledge of where the shoul- der hurt during swimming and which phase of the stroke provoked the injury, an anatomic

70% 18% I ,

Hand entry Forward reach Pull-through Middle pull-through Hand exit Middie recovery

Figure 1. Painful phases of the freestyle stroke. Seventy percent of painful symptoms are identified during the first half of pull-through. Eighteen percent of symptoms are identified during the first half of recovery.

THE PAINFUL SHOULDER IN THE SWIMMING ATHLETE 249

study was designed to determine the proxim- ity of soft tissues with skeletal tissue. Nine ca- daver shoulders were placed in the positions during the first half of pull-through, and cross- sections were taken. Five of the specimens ex- hibited bursal and intraarticular contact with the rotator cuff, two specimens demonstrated intraarticular contact only, and two demon- strated bursal contact only.E Three of the spec- imens that exhibited intraarticular and bursal contact also revealed the biceps tendon in con- tact with the coracoacromial arch. Two of the specimens with intra-articular cuff contact demonstrated greater tuberosity contact with the acromion. The site of intra-articular contact was commonest in the anterior-superior la- brum (five specimens), whereas the posterior- superior labrum was implicated to a lesser de- gree (three specimens). Cadaver specimens greatly simphfy the issue of shoulder problems in swimmers because they cannot account for the inflammation that would accompany the microtrauma of injury. The inflammation could cause more or different areas of contact. The cadavers cannot account for any patho- logic instability or muscular fatigue or substi- tution mechanics that may occur. Although simplified, this cadaver model allows a clini- cian to understand the multiplicity of ana- tomic contact areas (bursal and intra-articular areas) during the most painful phase of the freestyle stroke.

Stroke Analysis and Muscle Function

During the freestyle stroke, the upper tra- pezius, rhomboids, supraspinatus, middle del- toid, and anterior deltoid position the scapula and the humerus for hand entry and exit in the swimmer with normal shoulders (Fig. 2).26 The serratus anterior is continuously active throughout the stroke as it helps to position the scapula (along with the upper trapezius and rhomboids) for hand entry and exit and pulls the body over the arm (conceptually a reversal of origin and insertion). The subscap- ularis is also continuously active because the humerus is predominantly in internal rotation throughout the MonadU has demon- strated that 15% to 20% of a muscle's maximal voluntary contraction is the highest level at which sustained activity can occur without fa- tigue. Both the serratus anterior and the sub- scapularis appear susceptible to fatigue.

The pectoralis major and latissimus dorsi fire sequentially during middle-pull-through because they are the major source of the pro- pulsion force. The posterior deltoid follows these two muscles as it continues to pull the body over the arm and begins to lift the hu- merus out of the water at the end of pull- through. The teres minor functions with the pectoralis major as it forms a force couple to hold the head of the humerus back and to con-

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Rhomboids Upper Trapezius

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Figure 2. Primary movers at hand entry and exit. Normal shoulders: primary movers at hand entry and exit during the freestyle swimming stroke. (From Pink M, Perry J, et al: The normal shoulder during freestyle swimming: An electromyographic and cinematographic analysis of twelve muscles. Am J Sports Med 19:574, 1991; with permission.)

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trol the internal rotation force of the pectoralis major during propulsion.

The major difference in muscle action in swimmers with painful shoulders is that the serratus anterior is markedly depressed dur- ing middle-pull-through, whereas that of the rhomboids is markedly enhanced (Fig. 3A, B)J9 It is likely that the serratus anterior fa- tigues in swimmers with painful shoulders, producing an unstable scapula. To compen- sate, the rhomboids contract to stabilize the scapula. These two muscles are designed to function antagonistically. When the serratus anterior cannot perform, there is no muscle that can assist with a similar action. The only way the body can stabilize the scapula is to

1 ' 1 ' 1 1 1 1 1 ' 1 1 1 1 1 1 1 " 1 ' ' 1 ' '

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recruit the rhomboids. The optimal synchrony of firing seen in normal scapular rotation is disturbed at the time of propulsion.

Another asynchrony is the decrease in activ- ity of the subscapularis during midrecovery and an overall general increase in activity of the infraspinatus muscle (Fig. 3C, 0)J9 Oppos- ing muscles (an internal and an external rota- tor) change the intensity of their activity-the subscapularis decreases, and the infraspinatus increases. Similar to the serratus anterior, the subscapularis is susceptible to fatigue because of its continual activity in swimmers with nor- mal shoulders. Swimmers with painful shoul- ders may have fatigued their subscapularis. The subscapularis may also diminish its func-

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Figure 3. Normal and painful shoulders muscle activity during the freestyle stroke. Serratus anterior (A), rhomboids (B), subscapularis (C), and infraspi- natus (13). (From Scovazzo ML, Browne A, et al: The painful shoulder during freestyle swimming: An electromyographic and cinematographic analysis of 12 muscles. Am J Sports Med 19:581, 1991 ; with permission.)

Illustration continued on opposite page

THE PAINFUL SHOULDER IN THE SWIMMING ATHLETE 251

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tion to avoid the painful extremes of internal rotation, whereas the infraspinatus increases its activity to rotate externally the humerus for the same end goal.

During hand entry in swimmers with pain- ful shoulders, there is a decrease in activity in the anterior and middle deltoids and in the u p per trapezius and rhomboids. At hand exit, there is also a diminution of activity in these two heads of the deltoid. This reduced activity is related to the dropped elbow during recovery, early hand exit, and wider hand entry, which are discussed under subtle signs of injury.

There is no significant difference in the mus- cle firing of the primary muscles of propulsion (pectoralis major, latissimus dorsi, and poste- rior deltoid) when comparing swimmers with normal and painful shoulders. There is no sig- nificant difference in the muscle firing of the teres minor in swimmers with normal and

Normal - - - Painful -

painful shoulders. The muscles of propulsion as well as the pectoralis major and teres minor force couple are intact. The supraspinatus muscle also functions normally as it com- presses the head of the humerus in the glenoid.

This research suggests that the key muscle on which to focus for injury prevention and rehabilitation in competitive freestyle swim- mers is the serratus anterior. A stable scapula is paramount in preventing shoulder injuries, and the serratus anterior is the muscle that constantly fires to provide the necessary sta- bility. There is no other muscle that can sub- stitute for the serratus anterior and provide the same synchronous pattern of muscle firing. The rhomboids contract when the serratus an- terior fails, but the direction of pull is directly opposed to that of the serratus anterior, caus- ing asynchronous muscle action.

The subscapularis is another muscle on

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252 PINK & TIBONE

which to focus because it may also be suscep- tible to fatigue. It inserts close to the humeral axis of rotation, precisely holding the head of the glenoid fossa. It also forms the first layer of muscular anterior wall for joint protection. Because this muscle exhibits diminution of muscle activity in swimmers with painful shoulders, it requires attention from the clini- cian.

DIAGNOSIS

Originally, swimmer's shoulder, as de- scribed by Kennedy et a1,I6 was regarded as an outlet impingement syndrome, with impinge- ment of the rotator cuff tendons under the cor- acoacromial arch. It has been suggested, how- ever, that swimmers do not have a true outlet impingement but a tendinitis secondary to swimming as part of the increased laxity trans- lation that is present in this population. No- where is the relationship between impinge- ment, laxity, and instability more prevalent or more confusing than in the swimmer. Clini- cally, most swimmers have increased transla- tion and increased laxity of the shoulder; how- ever, only approximately 20% meet the criteria for generalized ligamentous laxity. Laxity is not the same as instability. Translations in the glenohumeral joint that are increased are a re- sult of joint laxity. If the same translations cause symptoms, this is shoulder instability. The amount of laxity present in the symptom- atic shoulder is usually the same as in the asymptomatic shoulder. Swimmers complain of pain not instability, and it is uncommon for them to have a true instability episode. (The exception is the backstroker, who commonly injures the anterior ligamentous structures.) The impingement that occurs is not outlet im- pingement but is impingement secondary to glenohumeral laxity, which places stress on the rotator cuff tendons. Also, there is a dysfunc- tion of the scapular muscles that disturbs the scapular humeral rhythm with improper positioning of the glenoid platform during exercise. This improper positioning places in- creased stress on the anterior capsular struc- tures, causing an increase of anterior transla- tion with a secondary impingement of the rotator cuff.

On examination, swimmers commonly have anterior or anterolateral shoulder tenderness. The impingement tests are positive, with the Hawkins test being positive in a greater num- ber of patients than the Neer test.25 Increased translations are usually present clinically in the anterior and inferior direction. Swimmers

should be evaluated for signs of generalized joint laxity, which includes being able to hy- perextend the elbows and knees, being able to place the palms to the floor with the knees ex- tended, being able to touch the thumb to the volar forearm, and being able to extend the metacarpophalangeal joint of the second or fifth finger greater than 90".

Normal swimmers usually do not have de- creased internal rotation range of motion as compared with external rotation. Even when present, it is not as dramatic as in other over- head athletes. There is usually not a marked posterior capsule tightness.

When the swimmer presents in the clinic or training room, radiographs are taken to rule out any unusual anatomic variant, but the ra- diographs are commonly normal. There is usu- ally no spur off the anterior acromion, and the anatomy is normal. CT scans are commonly of no value in the face of normal radiographs. MR imaging scans commonly show signal change in the rotator cuff tendon, but full- thickness rotator cuff tears or significant par- tial-thickness rotator cuff tears are rare. The MR imaging findings usually are confusing to the orthopedic surgeon and the athlete be- cause many asymptomatic shoulders have similar findings on MR imaging. In general, MR imaging scans are not beneficial in evalu- ating swimmer's shoulder. An exception may be backstroker's shoulder, in which a gadolin- ium-enhanced MR imaging scan may be use- ful in determining if there has been any ante- rior labral damage.

SUBTLE SIGNS OF INJURY

The earlier a potential injury is noted, the better the chance of recovery without signifi- cant anatomic damage. The subtle compensa- tory mechanics are most likely to be identified by the swimming coach. To be able to identify subtle signs of injury, the coach must first un- derstand the basics of normal mechanics of the normal and pathologic muscle firing patterns, which have been discussed.

One of the signs of potential injury is a dropped elbow in the recovery phase of the free- style stroke. By dropping the elbow, the swim- mer decreases the degree of humeral internal rotation. The internal rotation is painful, so by dropping the elbow, the swimmer is able to avoid the pain. Many coaches have responded to this sign by telling the swimmer to stop be- ing lazy or to keep the elbow up. Part of an educational plan for a coach would be to note

THE PALNF'UL SHOULDER IN THE SWIMMING ATHLETE 253

the yardage when the dropped elbow occurs and observe whether it begins to present itself earlier in the workout. The swimmer should be pulled from the workout when a dropped elbow is consistently evident and tested for impingement.

The coach can be taught the Hawkins test for impingement. Although the Hawkins test is not exactly the position the swimmer is sub- consciously trying to avoid by lowering the el- bow, it is similar enough that the coach can see that it is a test designed to elicit the pain that comes from pathology. As previously men- tioned, the Hawkins test more frequently de- tects shoulder pain in the swimmer than does the Neer or relocation test.25 The mechanics of the Hawkins test are more closely aligned with the mechanics of a swimmer's shoulder injury than other clinical diagnostic tests.

Rather than being lazy with a dropped el- bow, the swimmer is attempting to minimize the anatomic damage. The dropped elbow, or the decrease in humeral internal rotation, in swimmers with painful shoulders is sup- ported by electromyographic observations of more activity in the infra~pinatus.2~ The lower elbow also allows the swimmer to enter the water with a wider hand entry. If the observer misses the dropped elbow, the wider entry may be noted. The wider hand entry is sub- stantiated by altered electromyographic activ- ity in swimmers with pathologic s h o ~ l d e r s . ~ ~ These swimmers exhibit decreased activity in the anterior and middle deltoids along with the upper trapezius and rhomboids. The wider hand entry does not require as much scapular upward rotation or retraction, and, by defini- tion, it does not require as much humeral for- ward flexion.

The swimmer's pull may be a bit more asymmetric. The painful arm may not gener- ate forces equal to the contralateral side. The swimmer has difficulty staying in the center of the lane. Also the swimmer may compensate by decreasing the pull on the contralateral side or by changing the beat of the kick.

The swimmer may also allow the hand to exit the water early. Swimmers continue to propel themselves through the water in the later portion of the pull-through phase.I8 The swimmer with a painful shoulder may, how- ever, pull the arm out early and lose that por- tion of propulsion. As the swimmer pulls the hand out early, he or she is preparing for the dropped elbow during recovery phase that was discussed earlier.

Along with the early hand exit, the swim- mer may exhibit excessive body roll. The in-

creased body roll allows the hand to come out of the water with less shoulder hyperexten- sion. By avoiding the shoulder hyperexten- sion, the swimmer is actually avoiding the concomitant levering of the humeral head an- t e r i o r 1 y.

In that the serratus anterior is frequently a culprit of shoulder problems in the swimmer, it is worthwhile to observe the bilateral scap- ular symmetry (or asymmetry) on dry land. If a swimmer is suspected to have shoulder problems, the scapula position at rest and dur- ing motion can be telling. It is easiest to de- tect problems at the end of a workout, when the swimmer may be fatigued. Any scapular winging is a definite sign of problems. (The athlete is beyond a subtle sign of injury at this point.) Premature or excessive scapular ele- vation or upward rotation during flexion or abduction may be noted.

A study by Babyar2 noted that patients with painful and stiff shoulders exhibit excessive scapular vertical motion and no changes in horizontal motion. Likewise, McQuade et alZ1 have demonstrated excessive scapular motion in normal shoulders subjected to fatigue. The pathologic pattern in the swimmer is the same. The pattern could be caused by a diminution of serratus anterior function. If the serratus an- terior is not functioning adequately in the swimmer, it is not able to anchor the inferior angle of the scapula, and it cannot allow for a smooth movement. The upper trapezius ap- pears as if hyperactive, yet it is not hyperac- tive. It simply does not have the activity of the antagonistic muscle (serratus anterior) to con- trol the motion. The result is excessive or pre- mature scapular elevation and upward rota- tion. Historically, many clinicians have called this scapular asynchrony a lag. It is not a lag; rather, it is early and excessive motion. A naive eye (such as the swimmer watching himself or herself in the mirror fram the front as he or she elevates the arm) might detect this asynchrony as almost an early shoulder shrug motion. The lateral slide test as described by Kibler17 can be helpful. Three positions are tested: (1) with the arms at the side; (2) with hands on hips; and (3) with shoulder in abduction to 90" with maximal internal rotation. Measurements are made from the spine to the inferior medial bor- der of the scapula. An increase of lateral slide reveals subtle serratus weakness.

gested that an imbalance of the glenohumeral internal and external rotators is also a sign of injury. This normal balance is a ratio with the internal rotation component being stronger

Some authors1,3,10,11,14,16,20.27,28 have sug-

254 PINK&TIBONE

than the external rotation component. Strength research would mandate an approximate nor- mal ratio to be 3:2.3,4,5,12,33 The physiologic cross-sectional areas of the internal and exter- nal rotators would support the fact that inter- nal rotation should be more than external ro- tation. A pilot study reveals the physiologic cross-sectional area of the internal rotators to be approximately 53 cm2 and that of the exter- nal rotators to be approximately 16 cm3. These values would equate to a ratio 3.3:l. A true balance or a 1 : I ratio was never the intent of the human body. Also, it would be normal for the swimmer to adapt functionally to the re- quirements of swimming. As mentioned pre- viously, swimming is a sport of humeral inter- nal rotation with minimal need for external rotation. In one study comparing national competitive swimmers with controls, there was no significant difference in torque and to- tal work for the external rotators.28 The exter- nal rotators are not weak; it is just that the in- ternal rotators are functionally stronger. Also a separate study of 32 competitive swimmers demonstrated that shoulder pain and strength ratios were ~nrelated.~ The need to balance the humeral rotators is questionable.

Perhaps one of the best educational messa- ges the clinician can deliver to the swimmer and the coach is the differentiation between soreness and pain. Any athlete is familiar with muscle soreness and lives with soreness to a degree. Pain needs to be separated from sore- ness, however. Pain means pathology. Pain is telling an individual that he or she is causing damage to the anatomic structures. Once these structures are damaged, the pathology may not be reversible. When pain occurs, the ath- lete needs to minimize the damage and seek medical attention. Perhaps the best gift that cli- nicians could give to the training room of ath- letes is a banner with a big red circle and a line through the slogan "No pain, no gain" (Fig. 4).

CONSERVATIVE TREATMENT

The first step in conservative treatment is to eliminate acute inflammation. The earlier the injury is noted, the less inflammation, and the less time it takes to move past this step. Pad- dles, if they have been used, should be dis- couraged because they put undue stress on the shoulder and can lead to injury. A brief period of rest is beneficial to the swimmer; however, it is difficult to keep the competitive swimmer out of the pool for more than a few days. Non-

Figure 4. Use training room signs and banners to warn against erroneous messages.

steroidal anti-inflammatory drugs (NSAIDs) are used, usually in high doses, for 7 to 10 days. Swimmers with chronic shoulder pain are not usually kept on NSAIDs for more than a brief period of time. Each NSAID works dif- ferently in different patients, and a variety of medications may need to be tried to find the one that is most beneficial. Rarely a swimmer with a very hot shoulder may benefit from a methyl prednisolone dose pack (Medrol Do- sepak) to break the inflammatory cycle so that an exercise program can be started. Cortisone injections in the subacromial space are used judiciously. If the pain becomes severe, a cor- tisone injection may be beneficial if the athlete stops swimming for 2 to 3 weeks.

The swimmer can be in the pool with a kick board while the shoulder is recovering from the injection. The swimmer needs to be cau- tious, however, about the arm position on the kick board. Typically the arm position is one of full shoulder flexion with the kick board placed in front of the swimmer. This position may need to be modified to avoid the forward shoulder elevation. If this position cannot be modified without a great deal of awkward- ness, the swimmer can work out temporarily on a stationary bicycle. A stationary bicycle workout allows the swimmer to continue with cardiovascular training and with the self-per- ception of an active athlete while allowing the inflammatory process to decrease. While in this stage, modalities such as heat, ice, ultra- sound, or electrostimulation may be applied to hasten the process.

The next steps are to ensure adequate flexi- bility, strength, endurance, and scapulohu- meral rhythm. The administration of these steps is different from swimmer to swimmer and depends on the exact nature of the injury or weakness. Guidelines are presented to this process; however, they need to be augmented

THE PAINFUL SHOULDER IN THE SWIMMING ATHLETE 255

by a sharp clinical eye to know what to work and when to progress the process.

Stretching

The two most important words about stretching for the swimmer are be careful. As other authors have eloquently stated, ”swim- ming coaches and swimmers appear obsessed with the destruction of the anterior capsule of the shoulder j~ in t , ”~ and ”perverse stretching maneuvers . . . do not promote muscular flex- ibility, and they do not maintain adequate range of m~tion.”’~ Other than occasionally in the posterior capsule, swimmers do not tend to have joint tightness. The indication for stretching is limited. If a swimmer over- stretches the noncontractile tissues, they may not return to normal. If the capsule is over- stretched, the risk for instability and subse- quent injury is permanently enhanced. A gen- tle warm-up is sufficient to increase the blood flow, increase body temperature, and overall prepare the muscles for a workout.22

Partner stretching is especially disconcert- ing because vigorousness and potential dam- age have been noted. Another common stretch done by the swimmer is a wall stretch, which increases anterior shoulder laxity (Fig. 5). Knowledge of the two stretches not to do is

more important than knowledge of other stretches.

There are a few stretches that a clinician may find appropriate for some swimmers. Some swimmers have a posture of a forward head, rolled forward shoulders, and kyphotic tho- racic region. These swimmers may have a tight pectoralis minor or major. The trainer or ther- apist can stretch the muscles as shown in (Fig. 6) . Equally important to the specific stretch would be instruction in postural control and examination of any potential cervical prob- lems. These swimmers can also be given a chest stretch to do on their own (Fig. 7).

Swimmers with shoulder pain may occa- sionally present with posterior capsule tight- ness?* If the posterior capsule is excessively tight, it can push the humeral head anteriorly. These swimmers may exhibit early hand exit during the freestyle stroke, or excessive body roll. Both of these substitution mechanics are an attempt to minimize the humeral hyperex- tension that levers the head further anteriorly, causing pain. The posterior capsule stretch can be done by the clinician initially (Fig. 8A) and later can be taught to the swimmer to be done by himself or herself (Fig. 8B).

Strengthening Exercises

Research and clinical experience have pointed in the same direction for strengthen-

Figure 5. “Thou shalt not do this stretch.” Historically, many swimmers did this stretch; however, there is a great risk for this stretch to increase anterior shoulder instability.

256 PINK & TIBONE

\

Figure 6. Pectoralis stretch.

Figure 7. Chest stretch.

Figure 8. Posterior capsule stretch with a clinician (A) and self-administered (5). (A, From Pink MM, Screnar PM, et at: Injury prevention and rehabilitation in the upper extremity. In Jobe FW (ed): Operative Techniques in Upper Extremity Sports Injuries. St. Louis, Mosby- Year Book, 1996, p 5; with permission.)

THE PAINFUL SHOULDER IN THE SWIMMING ATHLETE 257

ing the shoulder muscles in the swimmer with an injury: primarily toward the serratus ante- rior and secondarily toward the subscapularis. The exercises that are included in this program are based on fine wire electromyographic re- ~earch.~*,~’ The exercises chosen have been shown to be optimal for these muscles. Be- cause no exercise recruits just one muscle, other muscles are worked simultaneously. If a careful examination reveals a deficit in mus- cles other than the serratus anterior and sub- scapularis, readers are encouraged to review the scientific literature for the optimal exer- cises to meet their patients’ needs.

The exercises are initiated with no load or low load, and the loads are gradually pro- gressed. The first exercises are done in an open chain. Once the muscle strength is in the good range, endurance exercise is initiated for short periods. As the endurance improves, the ath- lete can begin some sport-mimicking exercises, such as the swim bench. Once these exercises can be done without pain and with scapular rhythm, the swimmer can begin low mileage and slow-speed workouts. The individual can then progress performance within the limits of pain-free movement, no compensatory me- chanics, and good scapulohumeral rhythm at the end of the workout.

As the strengthening process is initiated, the clinician must insure that proper scapulohu- meral rhythm is maintained. At the first sign of loss of this rhythm, the degree of elevation of the exercise must be lowered, or the load must be lightened. As the athlete begins to do the exercises alone, they should be done in front of a mirror so that the athlete can see if he or she is doing them correctly.

Exercise should begin in the scapular plane. This plane allows for maximal congruency of the humeral head in the glenoid and the least stress on the capsule and ligaments.I5 The ex- ercises are first done without any weight, then at low elevations with a 2- or 3-lb weight. If the idea of low weights is met with mental re- sistance, swimmers can be reminded that they do not need bulk, but they need a stable shoul- der on which to build speed and endurance. They can gradually increase their strengthen- ing program to three sets of 15 repetitions throughout the range but still with a relatively low weight.

To perform the first exercise, the athlete stands with the arm in the scapular plane and the thumbs down (humeral internal rotation). As the arms are raised, they begin to rotate externally (thumb begins to rotate upward).

By the time the arms are at 70” of elevation, the thumb should be facing up (Fig. 9). The elbows stay straight throughout this exercise. It is rec- ommended that the exercise is simultaneously done with both arms so that any compensa- tory motions can be easily detected.

Once the individual can successfully do this exercise for three sets of 15 repetitions throughout the range without any weight, he or she can attempt it in the frontal and the co- ronal planes. The athlete can also start to add weight to elevation in the scapular plane. After the athlete can do all three planes with a 3-Ib weight and without compensatory mechanics, he or she can proceed to the modified military press.

The modified military press is performed in the seated position with the elbow close to the side (Fig. 10). The arms are raised straight overhead with the palms facing in. The elbow is kept in a straight line parallel to the body. Similar to the scapular plane exercise, this ex- ercise is first done without weights, then grad- ually progressed through low weights.

Another exercise is the four-count horizon- tal row. The four-count horizontal row is per- formed standing with bands or free weights. The first position is with the shoulder forward flexed 70” with maximal scapular protraction.

Figure 9. Elevation in the scapular plane.

258 PINK & TIBONE

I './ '

Figure 10. Military press.

The second position retracts the scapula. The third position brings the elbow in line with the plane of the body. The lust position slowing re- turns the arm to the first position (Fig. 11).

After the athlete can perform these open- chain exercises within the aforementioned pa- rameters (pain-free motion, no compensatory mechanics, and good scapulohumeral rhythm at the end of the workout), the athlete can be- gin a progression of push-ups with a plus. The major benefit of these exercises is the plus ma- neuver, which is at the top of the push-up. At the top of the push-up, the scapulae are spread protracted as far apart as possible; this creates an arch in the thoracic area. The gluteal and low back areas are kept low. Then the swim- mer lowers himself or herself to the ground, without lowering the body past the humerus. If the swimmer goes all the way to the ground, he or she causes the humeral head to be lev- ered anteriorly. Some therapists recommend that these exercises be done against a waII (i.e., a wall push-up). Because of the numerous compensatory techniques that can be em-

@

figure I I. Four-count horizontal row exercise: First position (A), second position (B), third position (C), and last position (return to first position).

THE P A I N R n SHOULDER IN THE SWIMMING ATHLETE 259

A B Figure 12. Push-up with a plus, on knees and hands (plus position) (A) and toes and hands (go no further toward the floor than a 90" angle at the elbow) (B).

ployed against a wall, however, the authors prefer to teach the exercise on the floor. The progression of the push-up with a plus be- gins with the athlete on the knees and elbows (Fig. 12A). Once the athlete gets the feel for the plus maneuver, he or she can progress to the knees and hands. Once this movement is done safely and correctly, the athlete can progress to doing the push-upwith a plus on tKe t&s (Fig. 1 2 . B).

The 'next exercise in the progression is the endurance exercise. An upper extremity er- gometer works well to develop scapular mus- cle endurance. For this exercise, the swimmer sits so that the shoulder is flexed about 100"

from the axis of the pedals with the elbow ex- tended when holding the pedals (Fig. 13A). The swimmer sits far away enough so that the elbows are extended fully and the scapulae are separated. The motion begins at a rhythmic, even pace with mild resistance. The elbows are bent for about half of the cycle and are ex- tended during the other half. The goal of the exercise is to work the muscles around the scapulae and shoulders as opposed to the el- bows. The scapulae should be protracted when the arm is extended and retracted when the arm is nearer to the body (Fig. 13B). The exercise can be initiated for about 1 minute and progressed gradually.

Figure 13. Upper extremity ergonometer. A, Arms are elevated to approximately 100". B, Scapulae should be protracted when the elbow is extended.

260 PINK & TIBONE

At this point, endurance for the subscapu- laris is introduced on an isokinetic device. As mentioned previously, this muscle is vulner- able to fatigue. Internal and external rotation exercises are performed with the arm at the side. The humerus is elevated forward about 10" to 20" to protect the anterior capsule. Iso- kinetic speeds of 180"/s and 240"/s are used.

About the same time as the endurance ex- ercises begin, the athlete can start activities on the swim bench. Because the swimmer is pain- free at this time, he or she also can return to a kick-board workout, with perhaps a few slow laps of the freestyle stroke. The swimmer con- tinues with the elevation exercises, modified military press, and push-up with a plus. Even- tually the swimmer returns to the complete workout at the prior intensity. It is hoped that the swimmer never gives up the exercise pro- gram because doing so can lead to recurrent shoulder problems.

SUMMARY

The ability to return a swimmer back to nor- mal is a blend of art and science. It entails a knowledge of normal mechanics, injury me- chanics, subtle signs of injury, diagnostic tools, and exercises specific to the injury. All of this knowledge is for naught, however, unless the clinician also possesses a sharp eye and a feel for the appropriate rehabilitation progression. The science gives a platform from which to se- lect the progression artfully. By applying the art and the science of swimming and medicine, clinicians can return swimmers back to the wa- ter in the minimal time with a low recurrence of injury.

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Address reprint requests to James E. Tibone, MD

Department of Orthopaedics University of Southern California

1510 San Pablo #322 Los Angeles, CA 90033