Download - The Throwing Shoulder
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.