Shoulder pain among tennis players is a widespread problem. This plague is likely a consequence of many things, most notably our cultural shift toward sitting, video games and computers. Kyphotic postures resultant of a routinely sedentary lifestyle place the shoulders of our weekend athletes in some very precarious positions on the court, particularly during the service motion. Although the serve exposes our clients to shoulder mayhem, they are not going to stop playing tennis, so we as therapists must be prepared to take on the challenge of keeping them healthy and pain free.

Here is the chronicle of a kyphotic tennis player named Suzie, a fictional character, yet quite representative of many of the clients we treat on a daily basis. It details her postural misadventures on and off court, and offers some treatment strategies to keep her out of pain and playing the sport she loves.

Suzie is a 34-year-old accomplished dentist and weekend tennis enthusiast. She has been suffering from pain in her right shoulder for many years. She recently has begun noticing a relative weakness in her right arm, with occasional right wrist pain. In spite of her recurrent pain, she never misses her much loved Saturday morning tennis camp. Subsequent to hitting a few shopping carts worth of forehands, backhands and serves, she typically heads to the gym for a 45 minute workout on the elliptical machine. While on the elliptical, she catches up on the news, watching the TV that is mounted to the wall five feet above her. At this point, it's probably redundant to say that her head has found itself four inches in front of her body.

The service motion involves many components that can leave Suzie vulnerable to injury, but for the purposes of this discussion, I will limit it to four main items: posture, biomechanics, anatomy and repetition.

Posture

Try slumping forward and then raise both arms overhead. Not happening, huh? When the thoracic spine is slumped forward, the shoulder loses its ability to flex completely, a very necessary component if you expect to serve overhead. Research by Janda suggests there is a group of postural muscles (i.e. upper traps, SCM, pecs) that are involved in tasks such as sitting or standing, additionally these muscles tend to become overactive and shorten.^1,2

Janda's work also pointed out that the antagonists of the postural muscles (i.e. deep neck flexors, rhomboids, mid and lower traps) tend to loose their ability to communicate with the CNS, and eventually become weak and inhibited. Upward rotation of the scapula is required for the service motion, this is primarily a function of the serratus anterior, rhomboids, mid and lower traps.³ Unfortunately for Suzie, these inhibited yet functionally necessary muscles will be of little assistance when she attempts any overhead motion. Without a stable scapular platform, the service action will be as effective as shooting a cannon off of a canoe. This begs the question, how is Suzie accomplishing this movement when her poor posture has precluded her from flexing her shoulder and recruiting key stabilizing muscles? According to the developer of the Functional Movement System, and author of the book Movement, Gray Cook, "the human system will migrate toward predictable patterns of movement in response to pain or in the presence of weakness, tightness or structural abnormality." In essence, her body has found different pathways to complete the task of serving. It doesn't really care about optimal movement; its priority is more about getting the job done. I'm wincing at the thought of the possible recruitment scenarios that are involved in her adaptive stroke production.

Anatomy

The human shoulder is the most mobile joint in the body.⁵ This mobility can lend itself to stability issues. Although ligaments and the labrum offer support, the true worker bees in stabilization of the GH joint are the rotator cuff muscles. The Supraspinatus, Infraspinatus, Subscapularis and Teres Minor (aka S.I.T.S.) are primarily responsible for keeping the head of the humerus from sliding around the glenoid fossa. These muscles perform many actions, the most clinically significant for our tennis player include the following:

• Supraspinatus and infraspinatus provide joint compression.
• Subscapularis and teres minor provide a downward pull to oppose the upward displacement of early deltoid action.
• Subscapularis offers anterior protection against excessive external rotation or extension.

Suzie's shoulder blades are in a protracted position, the cuff muscles attaching on to the scapula are now at a mechanical disadvantage. If the cuff muscles are not in ideal position to fire, her humeral head will begin to travel. Needless to say, this is more bad news for the health of her shoulder.

One of the most salient features of the GH joint, is the limited space under the hood of the acromion process. During the service motion, the humeral head and its overlying biceps tendon and rotator cuff must pass under the coraco-acromial arch. Any increase in the size of the structures (either by inflammation or hypertrophy) underneath the arch may lead to impingement.⁶ Considering Suzie's humeral head is probably shifting around within the fossa, the probability of an inflammatory response is likely, thus creating a perfect environment for impingement. Additionally, a decreased space available underneath the arch secondary to osteophyte formation of the acromion and fibrosis of the subacromial space may lead to impingement.⁶ To make matters worse, not all acromions are shaped exactly the same. There are three classifications of acromions. Type I, decent room under the hood. Type II, not bad, but the hood is a bit overhanging. Type III, this acromion is the devil. It has a big hook on the end limiting the capacity of the shoulder to flex without impinging on something. We can only hope that Suzie has some genetic luck on her side.

Biomechanics

A biomechanically sound service motion involves a sequence of perfectly timed force couplings and torques generated from the legs, hips and upper body.⁴ The entire kinetic chain, from the feet to the shoulder, shares in the power production of a serve. Even though the lower body is a large driver of power in a good serve, it is well documented that the greatest forces and moments are applied at the shoulder and overtime presents the risk of injury to the muscles of the rotator cuff, as well as the ligamentous and capsular structures.^3,4,5 If a technically proficient serve significantly loads the shoulder, consider the loading on Suzie's shoulder. Not to be critical, but her strokes resemble a rigid, muscling of the shoulder to the exclusion of all the great power generating muscles in the body. She has effectively eliminated three fourths of the kinetic chain, thereby increasing the reliance on her shoulder which will most assuredly lead to tissue overload.

The job of the cuff muscles in a tennis player is a complex one at best. For things to run smoothly, a balance must be struck between the concentric work to position and accelerate the arm, the eccentric work to stabilize and decelerate the shoulder, and the effective depression of the humeral head to avoid impingement in the overhead position.⁴ EMG analysis of a biomechanically efficient serve suggests that in the windup, cocking and acceleration phase of motion, the firing of the scapular stabilizers and anterior eccentric shoulder preceeds the firing of the rotator cuff.⁴ This spells more trouble for Suzie. Her load sequencing will be disturbed due to the inhibition of her scapular stabilizers, creating more opportunity for impingement.

Repetition

When a client comes into your office and complains of shoulder pain, they are less likely to blame their less than perfect service motion or their slumpy posture. More likely, they will say the culprit is that they slept on their shoulder "funny" or lifted something heavy in the garage. Dr. Shirley Sahrmann, author of Diagnosis and Treatment of Movement Impairment Syndromes, postulates that our repetitious movements and everyday activities are the culprits behind muscle imbalance and pain. If you have ever been to a tennis clinic, you will undoubtedly see a shopping cart filled with tennis balls. I imagine your aching to know how many tennis balls fit in one basket. The answer is 350. Let's presume that Suzie hits three shopping carts worth of serves, forehands and backhands. That is more than one thousand repeated offenses to her shoulder.

Let's sum up Suzie's situation thus far: Kyphotic posture + suspect anatomy + poor biomechanics + repetition = train wreck. Her posture is setting her up for chronic pain and dysfunction. Her FHP won't permit adequate shoulder flexion. Inhibition of the inferior scapular fixators has nixed the quality movement patterns necessary for the service motion. Her winged scapular position has rendered the S.I.T.S. muscles ineffective at keeping the humeral head in place, consequently the supraspinatus, subacromial bursa and biceps tendon are getting pummeled. Her chronic pain is affecting her energy levels and mood, finally she decides to go to the doctor who tells her she has a rotator cuff tear.

The truth is most of your tennis players have rotator cuff tears and often times they go completely unnoticed. Some of the most recent literature on pain suggests that tissue injury does not equal pain. One study examined the prevalence of rotator cuff tears and pain. The researchers took MRIs on the shoulders of 96 asymptomatic subjects and found cuff tears in 34% of the cases, with 54% of those older than 60.⁷ Yet, another study found that out of a sample size of 30 shoulders, there were absolutely no completely normal rotator cuffs in those under the age of 50.⁸ This suggests that non-enhanced magnetic resonance imaging may be of limited value in defining rotator cuff injury in a patient with shoulder pain unless a full-thickness rotator cuff tear is suspected. In chronic pain, special diagnostic tests of localized areas (for example, low back radiographs) are often normal, although the patient complains of pain. This research indicates that it is something other than the structural deficit that causes certain people to experience pain.

Suzie's doctor has followed up with her and is not recommending surgery, stating it is a very small partial thickness tear of the supraspinatus tendon, and considering her age, location of the tear and relatively good health, believes more conservative therapies are appropriate at this time. So, the million dollar question is, what can a massage therapist do for Suzie?

Treatment

Clearly, there is little we can do about fixing the tear to her tendon. I would say that our rotator cuff solution begins with improving her posture, thoracic spine mobility and her tissue quality. Janda believed that treatment should begin with the normalization of tight tissue prior to any type of strength training. Travell had similar thoughts, subscribing to the notion that trigger points need to be resolved before the strengthening phase of rehabilitation begins. A nice analog to their views is hitting the brakes in your car, while at the same time hitting the accelerator. You won't go very far, but once you release the brakes, you are off and running.

• Any muscle that internally rotates the shoulder, protracts the shoulder girdle or creates an elevation of the shoulder girdle, would be considered "brakes" in the case of the overhead athlete. The use of myofascial release, trigger point therapy and muscle energy techniques on the pecs, lat dorsi, teres major, biceps, upper traps and levator scapula, will go a long way in permitting a more optimal service motion.
• Studies have suggested that a single intervention session of soft tissue mobilization and PNF to the subscapularis was effective for producing immediate improvements in glenohumeral external rotation and overhead reach in patients with shoulder disorders.⁹ Get comfortable being in your client's arm pit. Remember, soft hands and go slow!
• Working the supraspinatus is gold with tennis players; however, it can be tricky to access, as the part that is getting beat up is under the acromion. While your client is prone or seated, it is important to traction the humerus downward to expose the tendonous attachments. Additionally, try putting your client in the handcuffed position, this should expose the tendon just anterior and inferior to the acromioclavicular joint.
• Gentle cross fiber friction to the tendinous attachments of the long head of the tricep, long head of the biceps, lats and the S.I.T.S.
• The infraspinatus is worth exploring for trigger points. I have yet to see a tennis player that didn't have trigger points in this muscle at some point in time.
• Further upstream, the likelihood your forward headed client is an upper chest breather is strong. Working on the SCM and the scalenes will provide tremendous relief. Coaching diaphragmatic breathing is an absolute necessity in resolving restrictive motor patterns of the upper body.
• Get your clients to mobilize their thoracic spine, often! Pick your favorite method (foam rolling, AIS etc.) and give them homework.

Once the soft tissue has responded to manual therapy, it is time to introduce your client to a person with corrective exercise experience. The biggest mistake clients can make once their pain has resolved is returning to tennis without strengthening the inhibited postural stabilizers and rotator cuff muscles. In Suzie's situation, the supraspinatis tear can lend itself to further instability that must be addressed in order to prevent the humeral head from shifting within the fossa. Manual therapy is just the beginning, if tennis players want to continue playing without chronic pain, they must re-educate these muscles to fire again with appropriate timing, strength and speed. Help your clients find corrective exercise specialists that are well versed in working with the special needs of overhead athletes.

Summary

Forward headed posture places our clients at a tremendous risk for injury particularly when they participate in sports involving movement which requires a perfectly organized body. As Suzie can attest, bad alignment coupled with repetitious poor loading of joints spells big time trouble for tennis players. Therapy directed toward optimizing posture, improving soft tissue quality, reclaiming strength of the scapular fixators and S.I.T.S. muscles, and establishing good movement patterns will give them a good chance at continuing to play tennis and will help prevent some very needless suffering.

References

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