9. MDI Definition
The presence of inferior
instability in combination with
anterior and or posterior
instability
10. Definitions
• MDI implies subluxation or dislocations in
at least two directions either anteriorly,
posteriorly, or inferiorly
• Usually, the patient experiences
symptoms in one direction, but the
examination reveals more directions of
instability
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12. MDI types
• Anterior-inferior dislocation with posterior
subluxation
• Posterior-inferior dislocation with anterior
subluxation
• Recurrent dislocation posterior and inferior
Neer and Foster
13. MDI Characteristics
• Relatively common
• Generally bilateral
• Atraumatic condition affecting
shoulder function
• Excessive translation in all
directions but with the
predominance of ONE direction,
typically anteroinferior or
posteroinferior.
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14. MDI Characteristics
• Usually in overhead
active sports
• gymnastics, swimming,
throwing, racquet sports
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16. MDI Characteristics
• NOT associated with severe trauma
Congenital hyperlaxity of the joint capsule
or generalized joint laxity in association
with failure of dynamic stabilizers and minor
trauma
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Ehlers-Danlos Syndrome
17. MDI clinical presentation
• Frank dislocations with minimum violence
often reduced by the patient
• Subluxations and positive apprehension
sign in one or more directions in a loose
joint individual usually teenager
• Pain and functional impairment in a loose
joint individual, the patient mainly
complaining for pain and not for instability
18. Types of dislocation
• Voluntary dislocation
• Involuntary dislocation
should be recognized early
19. Voluntary dislocation
• Patients with good muscle control who can
dislocate and relocate their shoulder at will
from an early age that may lead to gradual
strain of the capsule and loss of control of
the dislocations
• True voluntary dislocators with psychiatric
problems
20. MDI Diagnostic Tools
Highly clinical diagnosis
• History
• Clinical examination
• Marginal help of imaging studies
(plain radiographs, MRI, MRI-arthrography)
• Highly supportive:
– Examination under anesthesia (EUA)
– Arthroscopic findings
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21. MDI Clinical Examination
• Bilateral physical findings
• Usually, rotator cuff (dynamic stabilizers) weakness
• Drawer and load-shift tests (anterior and posterior)
reveal displacement with an elastic feeling
• Pathognomonic “sulcus sign”
• Apprehension test may be positive, usually in the
direction of the chief component of instability
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22. Clinical examination
• Usually vague symptoms with activity
• Associated conditions: collagen disorders
• Look for generalized hyper-elasticity
(thumbs can be hyperextended to the distal radius, elbow
hyperextended ,knee recurvatum)
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23. Clinical examination
SULCUS sign with the arm in adduction that
persists in external rotation or abduction is a
major clinical sign
Anterior and posterior load and sift tests
24. Examination Under Anesthesia
• To demonstrate increased
glenohumeral anterior,
posterior and inferior
translation
• Usually, symmetrical
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27. Treatment: Address all factors
• Dynamic stabilizers: rotator cuff and
scapula muscles
• Static stabilizers: plication of
capsuloligamentus stactures
28. treatment
• Open treatment first described by Neer as
the glenoid inferior capsular sift based
laterally on the humeral head
• Arthroscopic management was pioneered
by Gaspari using a transglenoid technique
29. Contraindications
for Surgical Treatment
• Voluntary shoulder instability
• Collagen disorders
(eg, Ehlers-Danlos syndrome, Marfan syndrome)
• Noncompliance with a supervised
rehabilitation program
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35. MDI Surgical Treatment
The goal is "addressing the capsular
laxity and redundancy to restore
anatomic capsuloligamentous tension
without overconstraining the shoulder."
[Caprise and Sekiya, 2006]
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39. Possible problems
• Axillary nerve injury
• Loose repair
• Healing problems
(collagen diseases: Ehlers-Danlos, Marfan)
• Postoperative noncompliance
• Overtensioning
is not a common problem
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40. Rehabilitation Program
• 0-3 weeks Relaxing phase
• 3-6 weeks Passive movements to ROM
• 6w – 3 m Assisted Active movement to ROM
• 3-6 m Active movement to ROM
• >4m Propioception improvements
• >4m Strengthening exercises
• >9 Return to sports
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41. What to expect
• Painless shoulder
• Full ROM
• No atrophies
• Return to the same sport level
Rowe scores:
78% excellent / good [Snyder, 2001]
75% excellent / good [Wolf, 1999]
88% excellent / good [Treacy, 2002]
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44. Conclusions
• Most patients present in their late teens
• Complaints of pain during athletic activities
or ADL
• Uncountable dislocations and subluxations
even at sleep reduced by the patient in a
tall thin loose joint individual
• Excessive ROM in more joints
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45. Conclusions
• Excesive translation of the joint anterior
posterior and inferior at clinical
examination with aprehension in one or
more directions
• At arthroscopy a patulous thin capsule
with few other findings.
46. Conclusion
• Treatment should address all factors of
instability mainly the dynamic stabilizers
with an aggressive rehabilitation program
and if this fails arthoscopic or open
capsulorraphy in order to reduce the
volume of the capsule