1. science
2. medicine
3. surgery

The Throwing Shoulder
Ryan P. Dunlay, M.D.
ORA Orthopedics
March 30, 2015
Anatomy of the Shoulder
Anatomy of the Shoulder
• Static ligamentous
restraints
• Superior GH ligament
• 0 degrees abduction
• Middle GH ligament
• 45 degrees abduction
• Inferior GH ligament
• 90 degrees abduction
• Anterior band most
important
Anatomy of the Shoulder
• Dynamic restraints
• Rotator cuff
• Compresses humeral
head into glenoid
• Increased muscle
tone increases
stability
• Most important in
mid-range of motion
• Lax capsule and
ligaments
Shoulder Stability
• Glenoid small and shallow
• 2.5 mm in depth
• Surface area ~1/3 of humeral
head
• Labrum adds static stability
• 50% of depth of fossa
• Increased contact area
• “Suction-cup” effect
• Resists 20N of lateral traction
• Harryman et al. JBJS-A 72, 1990.
Throwing Biomechanics &
Phases
• Near ball release the peak velocity of internal
rotation is 7,500 degrees/sec – fastest human
motion in sports
wind-up, early cocking phase, late cocking, early acceleration, deceleration
release, follow through
Pathophysiology of the
Throwing Shoulder
• Internal impingement – cocked position
results in impingement between posterior
superior labrum and undersurface of the cuff
(infraspinatus)
• “Peel back phenomenon” –
Morgan and Burkhart –
biceps feeds into
posterior superior
labrum and labrum
off of rim
Pathophysiology of the
Throwing Shoulder
• Biceps tendon labral complex creates shearing
force in late cocking – like “weed pulling”
• Long head of biceps tendon is controversial in
its function and impact on throwing
mechanics and velocity
• Stimulation of biceps at 90 degrees of
abduction does compress humeral
head into center of glenoid - Andrews
Clinical Diagnosis
• History is important
• MRI is gold standard – ABER view shows
IGHL, labrum, acromion, supraspinatus,
posterior labrum and infraspinatus
• “If you want an excuse to operate on a
throwing shoulder get an MRI”
• Andrews, Wilk et al – 37
asymptomatic MLB pitchers:
90% abnormal labrum, 89%
had abnormal RTC, 39%
humeral head changes
History and Physical Exam
• Pain is often the complaint and not instability
• Try to define when in the throwing phase the
pain is occurring or if it is after throwing
• Define number of pitches thrown or long
throws – position of athlete
• How long have symptoms been ongoing?
• Was there an acute injury?
• What point in the season
is the athlete?
History and Physical Exam
• RTC strength and ROM active and passive
• Look for winging in scapulothoracic ROM
• Active compression (O’Brien’s) and resisted
supinated ER test – validated for anterior and
superior labral injuries
• Sulcus sign and patholaxity exam
• Assess stability in the supine position with
comparison to contralateral side
• Jobe’s apprehension and relocation tests
Physical Exam
• ROM, strength – Abd, ER, IR, Abd – ER, Abd
– IR
• Always examine scapula motion from
posterior – look for
winging/protraction/upward tilting
• Forced Elevation/Impingement
• SLAP – O’driscoll’s shear test, O’Brien’s
• Biceps – TTP, Throwing Test, Speed’s,
Yerguson’s
• Supine exam
Physical Exam
• Supine IR, ER – can palpate coracoid to
determine when scapula moves to document
ROM; Relocation test – positive in internal
impingement
• Quantify Total ROM and ER/IR difference
from side to side
• Anterior and Posterior laxity
tests while loading
Physical Exam
Physical Exam
Whipple Test
• Scapular position at rest and then manually
retracted
• Check and compare side to side difference
• Whipple tests supraspinatus with and
without retraction of the scapula and is good
test for scapular dyskinesia
• Dynamic labral shear test for instability
• O’Brien’s test
Diagnostic Imaging
• Plain radiographs, true AP, scapular Y, and
axillary views (Velpeau view)
• Humeral head translation relative to the
glenoid at rest is suggestive
of insufficiency of anteroinferior
stabilizing structures
• CT scan may be useful in case of
bone loss assessment
• MRI is mainstay
Diagnostic Imaging
• Axillary radiographs yield the most information
• CT scan for glenoid hypoplasia, retroversion,
bone loss
• MRI – particularly MRA are mainstay for
capsulolabral pathology
MRI – ABER position
4 components of internal
impingement
•
•
•
•
Excessive horizontal extension – Jobe
Over rotation
Increased glenohumeral rotation
GIRD
The Disabled Throwing
Shoulder
• In order to throw increased laxity becomes a
necessity
• When does laxity become instability?
• May be adaptations to the sport
Current Concepts – Wilk et al
• Laxity becomes a necessity
• There are congenital adaptive changes to the
bone and soft tissue structures that must be
present to be effective
• Muscle balance is very important in
preventing injury
• Total Arc of Motion (TAM) is important
concept
• GIRD is very dynamic and may change daily
Core Strength
• Trunk strength and stability that allows the
lower extremity power to transmit through
the kinetic chain to the arm (Kibler’s kinetic
chain)
• Calf is first muscle to contract
• Children and adolescents often lack
development of this strength which
puts them at increased risk of injury
The Scapula
• Scapula position is key
• Scapula retraction places arm in position for
maximal RTC function
• Core exercises maintain scapular retraction
and allow progression of forces through the
kinetic chain
• Proper mechanics and posture of the scapula
protects the shoulder and, therefore, the
elbow from increased strain and risk for
damage
Decision Making in
Throwing Shoulder
• Pathophysiology is multifocal
• Surgery is last resort and should be done only
after failed nonoperative treatment
Athlete <12
•
•
•
•
Usually fatigue and overuse/dyskinesia
Almost never need an operation
Rehab with cross training
Low weight and perfect form exercises with
avoidance of high weight and impact
activities
• Throwing programs and keep close track of
pitch counts
• Pitch counts: 100 max (50 twice a week)/wk
15-17 yo: 75 twice per wk; 18>: 100 total/wk
Athlete 12-15
•
•
•
•
Due to muscle imbalance
Look at posture & pay attention to scapula
Check mechanics
Use integrated exercises and focus on core
strength – strengthening from the ground up
and avoid surgery
Athlete 15-older
• This patient population may need surgery
and are more likely to have real pathology
• Internal impingement is common and pay
attention to labrum and cuff
• Don’t change principals of rehab
• Remember that all throwing shoulders are
unstable and surgery is only offered when
tipped over the edge and all else has failed
Rehabilitation
• Dynamic stabilization and proprioception
NM control important
• Dominant shoulder ER usually weaker – 6878% of the other side
• End range stability is functional for these
athletes
• Rhythmic stabilization working toward end
range exercises are beneficial with
pertubation
• Layering exercises to create more dynamic
stabilization
Rehabilitation
• Postural correction program to involve
improved soft tissue flexibility
• Pec Minor stretches
• Rhomboids/Trap strengthening
• Neuromuscular control drills (layering)
• Proprioception exercises for scapula
• Stability ball is good for scapula exercises –
very dynamic and core based
• Wilk’s Thrower’s 10/12 Exercises
Rehabilitation
• Kibler exercises – robber exercises
• Wall circles
• Serratus for protraction with wall exercises –
add resistance once technique is sound
• Planks
• Stretching pec minor
Rehabilitation – Phase I
• Phase I – Controlled rest with passive motion,
gentle active ROM with avoidance of
abduction ER, impingement positions
• Ice, compression
• Work on core, hips, scapula
• Taping, posture, etc.
• Should be pain free
Rehabilitation – Phase II
• Phase II–Integrated rehab with low weight
with upper extremity plyometrics and Wilk’s
10/12 exercises
• Monitor mechanics and focus on scapula
control throughout upper
extremity plyos and early
resistance training
Rehabilitation – Phase III &
beyond
• Phase III-Continued conditioning and
strengthening and return to throw program
• Return to throw starts with short distances
(25-50 feet) soft toss with <50 throws and
focus on technique, “crow hop”
• Should be pain free – different than soreness
• Progress to 100 feet with no pain on flat
ground
• Mound work at 50%-75%-100% over time
• Continue therapy 1-2 months into season
Surgical Treatment
• Arthroscopic
• Always examine intraop and
postop
• Goal is to restore anatomy – repair
labrum, restore bone loss,
address intra-articular pathology
• High threshold to repair cuff –
• Debridement of cuff preferred
• Biceps tenodesis may be as
beneficial or more so than
labral repair
Surgical Treatment
• DO NOT OVERTIGHTEN THE SHOULDER!
• Less is more in the throwing shoulder and this
underscores importance of preoperative eval
• Many shoulders will have multiple
intraop pathology – address the
causative pathology
• Biceps tenodesis of type II and IV
SLAP tears can result in good
(up to %90) return to the same
level of activity (Gottschalk AJSM 2014
Surgery
Take Home
Points/Recommendations
• The shoulder is a complex structure with dynamic
and static restraints
• The stress placed on the shoulder during throwing
requires a delicate balance between laxity and
strength
• The kinetic chain is extremely important to successful
treatment of the disabled throwing shoulder
• A chance to cut is not a chance to cure by and large
with regard to the throwing shoulder and
overtightening can end a throwing career
Thank You !!