Michael D. Satterley PT, DPT, CIMT, CSCS

Tidewater Physical Therapy, Inc.

Oyster Point Physical Therapy Clinic in Newport News, Va.

www.tpti.com

THE THROWING SHOULDER: PREVENTING OVER-USE INJURIES

AGENDA• Statistics on Throwing Injuries

• Anatomy of the Shoulder Girdle

• Biomechanics of Pitching

• Overuse in Throwing

• Common Trouble Areas

• Preventative Exercises

STATISTICS ON THROWING INJURIES• High Incidence of Arm Pain in Youth Baseball Pitchers

• Each year 6 out of 10 young pitchers injure their elbow

• Approx 50% of participants in 2002 study of youth pitchers reported elbow or shoulder pain at least once during season

• 15% of college-level pitchers say that troubles in their current performance are based on injuries they received when they played youth baseball

• Number of Throws and Length of Season Increases Risk of Pain and Surgery

• Risk of pain increases if threw more than 75 pitches per game and more than 600 pitches per season

• Pitchers who averaged more than 80 pitches per appearance were nearly 4 times more likely to require surgery

• Pitchers who pitched competitively more than 8 months per year were 5 times more likely to require surgery

ANATOMY OF THE SHOULDER GIRDLE• Joints

• Glenohumeral Joint

• Scapulothoracic Joint

• Thoracic Spine

• Sternoclavicular Joint

• Acromioclavicular Joint

• Ball and Socket Joint

• Allows for large ROM in the shoulder girdle

• Glenoid Fossa

• Head of Humerus

• Acromion

• Supraspinatus Tendon

• Subacromial Bursa

• Latissimus Dorsi

• Impingement Syndrome

GLENOHUMERAL JOINT

• Not a true joint

• Positions the Glenohumeral Joint for overhead throwing

• Rotator Cuff Muscles

• Supraspinatus

• Infraspinatus

• Subscapularis

• Teres Minor

• Teres Major

• Serratus Anterior

SCAPULOTHORACIC JOINT

• Posture

• Needs to extend and rotate well

• Many muscles used in throwing at the shoulder girdle originate on the spine

• Rhomboids

• Lower Trapezius

• Upper Trapezius

• Middle Trapezius

• Interplay with ribs

THORACIC SPINE

• Not a huge contributor

• Connects to shoulder girdle via clavicle

STERNOCLAVICULAR JOINT

• Connection of Clavicle to Acromion

• ACJ Sprain

• Shoulder Separation

ACROMIOCLAVICULAR JOINT

• Windup and Stride

• Early Cocking and Stride

• Late Cocking

• Acceleration

• Deceleration

• Follow-Through

BIOMECHANICS OF PITCHING

• Positions body to optimally generate forces and power required to achieve top velocity

• If pitcher’s body and momentum fall forward prematurely, kinetic chain will be disrupted and greater shoulder force will be required to propel ball at top velocity

WINDUP AND STRIDE

• Begins once lead leg reaches max height and ball is removed from glove

• Ends when lead foot contacts pitching mound

• Stride allows for longer time for trunk motions to occur, which allows for increased energy production for transfer to upper extremity

• Front foot is planted slightly to third-base (RH)

• Pelvic rotation followed by upper trunk rotation

• Shoulder externally rotates and trunk arches

• Stance leg glute max fires to maintain slight dominant-sided extension and provide pelvic and trunk stability during coiling

EARLY COCKING AND STRIDE

• Occurs between lead foot contact and point of max ER of throwing shoulder

• Pelvis reaches max rotation and upper torso continues to rotate

• Max shoulder IR torque occurs just before max shoulder ER

• Increased amounts of shoulder ER help to allow the accelerating forces to act over longest distance, allowing greater pre-stretch and elastic energy transfer to ball during acceleration

• As shoulder approches max ER, subscapularis, pec major, and lats are eccentrically contracting, applying stabilizing anterior force to GHJ, and halting ER

• Upward rotatation of scapula important for 80 to 100 degrees of humeral abduction in throwing position – no impingement

LATE COCKING

• Time between max ER of shoulder and ball release

• Trunk continues to rotate and tilt, initiating transfer of potential energy through upper extremity

• Increased forward trunk tilt allows pitching extremity to accelerate through a greater distance, allowing more force to be transferred to ball

• Subscapularis reaches max activity during this phase along with pec major and lats, producing violent IR

• Serratus anterior protracts scapula to maintain stable base as humerus undergoes violent IR

ACCELERATION

• Occurs between ball release and max humeral IR and elbow extension

• Most violent phase of throwing cycle, resulting in greatest amount of joint loading encountered during throwing

• Posterior shoulder soft tissues (teres minor, infraspinatus, and posterior deltoid) dissipate these enourmous forces during acceleration phase as arm continues to adduct and IR

• Likely responsible for posterior capsular and soft tissue retraction commonly seen in throwing and for GHJ IR deficit seen in pitchers

• Trapezius, rhomboids, and serratus anterior assist in stabilizing scapula

DECELERATION

• Body continues to move forward with arm until motion is ceased

• Culminates with pitcher in fielding position

• Unlikely culprit for injury due to decreased joint loading and minimal forces

FOLLOW-THROUGH

OVERUSE IN THROWING• Fatigue

• Pitch Count

• Pitchers rely less on lower body and more on arms as they fatigue

• Less maximum shoulder ER and knee flexion at ball release

• Slightly more upright trunk position at ball release

• As low as 2 MPH difference in velocity from 1st to last inning considered significant

• Poor ball location

FATIGUE

• Should also be used as a guide in determining fatigue

• Little League Baseball pitcher regulation

• Catcher is a repetitive throw risk too

• Pitcher throwing 41 pitches or more cannot catch for remainder of day

• Catcher for 4 or more innings not eligible to pitch for that calendar day

Age Pitches per Day

17-18 105

13-16 95

11-12 85

10 and under 75

PITCH COUNT

COMMON TROUBLE AREAS• Shoulder ROM

• Joint Laxity

• Scapular Position

• Muscular Strength

• Proprioception

• Most overhead throwers display excessive ER vs. decreased IR at 90 degrees abduction

• Adolescent players

• Most dramatic at 13-14 years of age

• Why?

• Bony adaptations

• Anterior capsule laxity, posterior capsule tightness

• Large eccentric forces in external rotators during deceleration phase

• Infraspinatus and teres minor

SHOULDER ROM

• Excessive motion usually found in GHJ

• Excessive ER due to anterior capsule laxity

• Repetitive throwing or congenital

JOINT LAXITY

• Alterations in resting position may contribute to injury

• Anterior tilt and protraction

• Protracted and anteriorly tilted position

• May be normal adaptation to throwing and can be progressive

• Correlated with increase in shoulder IR

• Correlated to significant decrease in significant decrease in serratus anterior and lower trapezius strength

SCAPULAR POSITION

• Rotator Cuff Fatigue

• Loss of abduction strength through season

• Inability to center and stabilite GHJ

• Subacromial impingement

• Timing must be considered when assessing strength

• Profound weakness on manual strength testing 2 days following a start

• Also at end of season

• Again pitch count and rest days are important as season continues

MUSCULAR STRENGTH

• Where various parts of the body are located in relation to one another

• Those with capsular laxity and excessive ROM must rely on this to dynamically stabilize the GHJ

• Especially important at end ranges of motion

• Significantly decreases after throwing to fatigue

• Deficits return to normal within 10 minutes after throwing

PROPRIOCEPTION

• Goal is to prevent repetitive injury, not to necessarily improve performance

• Must focus on trouble areas

• Proper Shoulder/Spinal ROM

• Scapular Positioning/Stability

• Balanced Strength

• Proprioception

PREVENTATIVE EXERCISES

PREVENTATIVE EXERCISES• Proper Shoulder/Spinal ROM

• Sleeper Stretch

• Standing Cross-Arm Stretch

• Seated Mid-Back Rotational Stretch

• Quadruped Opposite Elbow/Knee Touches

• Sleeper Stretch

• 3x for 30 seconds

• Do not stretch through pain

PREVENTATIVE EXERCISES

• Standing Cross-Arm Stretch

• 3x for 30 seconds

• Do not stretch through pain

PREVENTATIVE EXERCISES

• Seated Mid-back Rotational Stretch

• 3x for 30 seconds

• Do not stretch through pain

PREVENTATIVE EXERCISES

• Quadruped Opposite Knee/Elbow

• 2 sets of 10 reps

• Slow and in control

• Be sure to actually touch the elbow to the knee

PREVENTATIVE EXERCISES

PREVENTATIVE EXERCISES• Scapular Positioning/Stability

• Bodyweight Rows

• Bent Over Rows

• Band Standing Rows

• Prone Shoulder Circuit

• Bodyweight Rows

• 3-4 sets of 10 reps

PREVENTATIVE EXERCISES

• Bent Over One Arm Rows

• 2 sets of 10 reps

• Focus on bringing your elbow back

• Making the medial part of your scapula go towards your spine

PREVENTATIVE EXERCISES

• Standing Band Rows

• 2 sets of 10 reps

• Trying to squeeze your shoulder blades together

PREVENTATIVE EXERCISES

• Prone Shoulder Circuit

• Y

• T

• W

• L

• 2 sets of 10 reps

• Hold at the top for 2 seconds

• Trying to squeeze shoulder blades on each

PREVENTATIVE EXERCISES

• Prone Shoulder Circuit

• Y

• T

• W

• L

• 2 sets of 10 reps

• Hold at the top for 2 seconds

• Trying to squeeze shoulder blades on each

PREVENTATIVE EXERCISES

PREVENTATIVE EXERCISES• Balanced Strength

• Pull-ups/Hangs

• Reverse Shrugs/Chair Dips

• High Rows

• Push-ups/Bosu

• Bench Presses

• Shoulder Presses

• Plank Holds

• Pull-ups/Hangs

• If you can’t do more than 5 pull-ups at a time, try hangs 5 times for as long as you can

• Ideally, 3-4 sets of 10 reps

• Great exercise to battle impingement

PREVENTATIVE EXERCISES

• Reverse Shrugs/Chair Press Ups

• Great for promoting scapular stability

• If reverse shrugs are too easy with heavy resistance band, try chair dips

• 2 sets of 10 reps

• Can do chair press-ups for a hold

PREVENTATIVE EXERCISES

• High Rows

• Focusing on scapular squeeze

• Make sure elbows are getting behind the torso

• 2 sets of 10 reps

PREVENTATIVE EXERCISES

• Push-ups/Bosu Push-ups

• Nose to floor

• 2 sets of 20

• If too easy, try Bosu Push-ups

PREVENTATIVE EXERCISES

• Bench Presses

• Bar or Free Weights

• Free Weights harder

• Makes you stabilize independently

• Try alternating arms or holding 1 high, while repping the other

• 4 sets of 10 reps

PREVENTATIVE EXERCISES

• Shoulder Presses

• Bar or Free Weights

• Alternating or Holds

• 3-4 sets of 10 reps

PREVENTATIVE EXERCISES

• Plank Holds

• Focus on getting in solid, stable position and holding

• Great for the core and shoulder girdle

• Can do 2 sets of 10 with at least 10 second holds

• Or, can do 3-5 minutes total and hold for as long as you can

PREVENTATIVE EXERCISES

PREVENTATIVE EXERCISES• Proprioception

• Rhythmic Stabilization Drills

• Weightbearing

• Quadruped Position

• Non-weightbearing

• Late Cocking

• Acceleration

• Deceleration

• Plyometric Deceleration Ball Flips

• Weight-bearing Rhythmic Stabilization

• Alternating forces applied to all sides of the arm to try to slightly push the athlete off balance

• Non-specific pattern

• Usually done for time

• 30 – 60 seconds

PREVENTATIVE EXERCISES

• Non-Weightbearing Rhythmic Stabilization

• Late Cocking

• Acceleration

• Deceleration

PREVENTATIVE EXERCISES

• Plyometric Deceleration Ball Flips

• Start with very light baseball-sized med ball

• Progress to weight that is pain-free and maintains fluid motion in deceleration and flip back

• 4 sets of 10 reps

PREVENTATIVE EXERCISES

SUMMARY• Overhand throwing is a very violent motion

• We need to make sure all joints are moving correctly and have well-balanced strength

• “Coaches have to watch for what they don’t want to see and listen to what they don’t want to hear.”

• John Madden

• We must pay attention to athletes’ verbal complaints as well as signs of fatigue to avoid injury

• Be proactive and institute preventative exercises into your warm-up routines

• Staying injury free is the key to a successful sports season

COMMENTS AND QUESTIONS

REFERENCES• Corrao M, Kolber MJ, Wilson SH. Addressing Posterior Shoulder Tightness in the Athletic Population. Strength

and Conditioning Journal. 2009; 31(6): 61-65.

• Seroyer ST, Nho SJ, Bach BR, et al. The Kinetic Chain in Overhand Pitching: Its Potential Role for Performance Enhancement and Injury Prevention. Sports Health: A Multidisciplinary Approach. 2010; 2(2): 135-146.

• Fortenbaugh D, Fleisig GS, Andrews JR. Baseball Pitching Biomechanics in Relation to Injury Risk and Performance. Sports Health: A Multidisciplinary Approach. 2009; 1(4): 314-320.

• Reinhold MM, Gill TJ. Current Concepts in the Evaluation and Treatment of the Shoulder in Overhead Throwing Athletes, Part 1: Physical Characteristics and Clinical Examination. Sports Health: A Multidisciplinary Approach. 2010; 2(1): 39-50.

• Fleisig GS, Bolt B, Fortenbaugh D, et al. Biomechanical Comparison of Baseball Pitching and Long-Toss: Implications for Training and Rehabilitation. Journal of Orthopedic and Sports Physical Therapy. 2011; 41(5): 296-303.

• Reinhold MM, Gill TJ, Wilk KE, et al. Current Concepts in the Evaluation and Treatment of the Shoulder in Overhead Throwing Athletes, Part 2: Injury Prevention and Treatment. Sports Health: A Multidisciplinary Approach. 2010; 2(2): 101-115.

• Cook G, Burton L, Kiesel K, et al. Movement: Functional Movement Systems: Screening, Assessment and Corrective Strategies. Aptos, CA: On Target Publications; 2010.