Shoulder Joint Dislocations

Glenohumeral Luxations (Shoulder Dislocations)

A glenohumeral luxation is the complete and permanent loss of contact between the humeralhead and the glenoid cavity of the scapula, involving capsulo-ligamentous lesions.

Objectives

• Define shoulder luxation.

• Describe clinical signs (inspection & palpation) of anterior shoulder luxation.

• Identify radiological signsand anatomical varieties of anterior shoulder luxation.

• Describe clinical signs of posterior shoulder luxation.

• Cite reduction techniques.

• Describe the Kocher reduction technique.

Generalities

• Definition: Complete and permanent loss of contact between the humeral head and glenoid due to capsulo-ligamentous lesions.

• Clinical Importance:

  • Emergency traumatology+++.

  • Frequency: 11% of shoulder traumas, prevalent in young males.

  • Anterior variety+++.

  • High risk of recurrence.

• Anatomy & Biomechanics:

  • Shoulder: highly mobile but unstable joint.

  • Humeral head: 1/3 sphere.

  • Glenoid: shallow, deepened by the glenoid labrum.

  • Stability provided by capsule, ligaments, andmuscles.

  • Functional mobility: antepulsion, retropulsion, adduction, abduction, axial rotation, circumduction.

• Anatomopathology:

  • Etiologies: Sports, domestic accidents, occupational accidents, roadaccidents, seizures, electrocution.

  • Mechanisms:

    • Direct: Fall on the shoulder, posterior impact.

    • Indirect: Abduction and external rotation, forced external rotation with abduction, or traction on thearm.

    • Recurrences: easier mechanisms.

  • Antero-internal luxation:

    • Constant lesions: Capsular-ligamentous rupture (tear or detachment), labrumlesion.

    • Associated lesions: Glenoid rim fracture, Hill-Sachs lesion (cephalic notch), rotator cuff rupture, greater tuberosity fracture.

Clinical Signs:
Typical Description: Antero-Internal Glenohumeral Luxation

Interrogation

• Trauma: Time, circumstances, mechanism.

• Patient History: Civil status, past medical history.

• Complaints:Acute pain, functional incapacity (IFA).

Clinical Examination

Inspection

• Patient's attitude: Upper limb trauma posture.

• Frontal view:

  • Acromial prominence (Epaulette sign).

  • External "axe strike" (hollow).

  • Obliteration of the delto-pectoral sulcus.

  • Arm in abduction and external rotation.

• Profile view: Widening of the shoulder contour.

• Dorsal view: Prominent spine and acromion.

Palpation

• Acute tenderness+++.

• Empty subacromial space / empty glenoid cavity.

• Anterior position of humeral head:

  • Palpable in the axillary hollow.

  • Obscuring the coracoid process.

  • Always moves with humeralmovements.

• Inability to adduct the elbow to the body / Berger's sign (elastic abduction).

• Deltoid region sensation: Axillary nerve (circumflex) assessment.

• Hand motor function tests:

  • Wrist extension = radial nerve.

  • Thumb opposition = median nerve.

  • Finger abduction/adduction = ulnar nerve.

• Distal pulse palpation.

Medical Imaging

• Standard Radiography (if possible before reduction):

  • Incidences: APand Lamy profile.

  • Results: Humeral head medially displaced, displacement severity (extra-coracoid, sub-coracoid, intra-coracoid), search for associated bone lesions.

  • Confirmation of reduction.

• CT Scan: Confirms diagnosis, detects associated lesions.

Evolution

• Favorable: Stable reduction, healing after 3 weeks of immobilization.

• Unfavorable:

  • Irreducibility.

  • Instability.

  • Axillary nerve palsy.

  • Brachial plexus injury (subscapular nerve).

  • Axillary vascular lesions.

  • Associated fractures.

  • Rotator cuff rupture.

Clinical Forms

Posterior Luxations

• 1-4% of shoulder luxations, often unrecognized (2/3 cases), leading to chronic luxations.

• Circumstances: Seizures, electrocution,direct anterior impact.

• Clinical signs:

  • Characteristic internal rotation attitude.

  • Prominence of coracoid anteriorly and humeral head posteriorly.

  • Flattening of the deltoid.

  • Deficit inactive & passive external rotation.

  • Signe de l'aumône (inability to supinate elbow in extension).

  • Any loss of external rotation after an accident or seizure must be considered a posterior luxation until proven otherwiseradiographically.

• Radiography: AP and Lamy profile and/or axillary profile.

  • AP: Discreet but suggestive signs – disappearance/asymmetric widening of joint space, decreased acromio-humeral space, loss of humeral head sphericity (double contour), Mac Laughlin's anterior humeral notch, internal rotation in all views.

  • Lamy or axillary profile: Visualizes head behind the glenoid.

Luxatio Erecta

• Clinical: Vicious locked attitude in abduction between 110 and 160°.

• Radiology: Humerus parallel to the scapular spine.

Subluxations and Unnoticed Luxations

• Radiographic stigmata (fracture of antero-inferior glenoid rim, humeral notch).

• Diagnosis often established by arthroscan showing anterior capsulo-ligamentous lesions.

Recurrent Luxations

• Clinical history:

  • After a first luxation, series of luxations at varying intervals.

  • Triggered by increasingly minimal trauma.

  • Sometimes luxation during sleep.

  • Easy to reduce, even by the patient.

• Radiography: Osseous abnormalities.

  • Glenoid malformation: global atrophy, erosion of antero-inferior rim.

  • Humeral head malformation: Malgaine's notch.

Irreducible and Chronic Luxations

• Irreducibility: Due to incarcerated bone fragment, humeral head impaction on glenoid, or rare rotator cuff incarceration.

• Incoercible Luxations: Recurrence immediately after reduction, potentiallydue to a large associated glenoid fracture.

Complicated Forms

• Fractures of the greater tuberosity.

• Glenoid fracture.

• Fracture-luxations: antero-internal luxations associated with surgical or anatomical neckfractures.

Diagnosis

Positive Diagnosis

• Interrogation / circumstances of occurrence.

• Clinical examination.

• Radiology confirms diagnosis and specifies anatomical variety.

Differential Diagnosis

• Exclude: Fractures of the proximal humerus, tumors of the proximal humerus.

Treatment

Goal

• Restore normal jointrelationships.

• Achieve a pain-free, mobile, and functional shoulder.

• Prevent and/or treat complications.

Means and Methods

Reduction

• Anterior Luxations:

  • Abolish Hippocratic technique (foot in axilla) - considered too traumatic.

  • Milch technique: Arm in 150° abduction.

  • Kocher technique: Elbow medially, can be traumatic.

  • Kocher Technique Steps: Traction - External Rotation - Adduction - Internal Rotation

• Posterior Luxations: Traction - Abduction - Internal Rotation - External Rotation

Immobilization

Rehabilitation

Osteosynthesis: Screws, pins, steel wires.

Indications

• Pure Glenohumeral Luxation: Reduction then 3 weeks immobilization.

• Associated Lesions:

  • Greater Tuberosity Fracture: Reduction + contention. Screwing if diastasis ≥ 10 mm.

  • Anterior Glenoid Fracture:Surgical treatment if displacement after reduction.

  • Fracture-Luxations: Enucleation, screw fixation, prosthesis.

• Recurrent Anterior Luxations:

  • Capsuloplasty (Bankart repair).

  • Anterior bone block (Latarjet procedure).

Conclusion

• Unstable articulation.

• High frequency+++.

• Urgent management.

• Search for associated lesions.

Acromioclavicular Luxation

Clinical Diagnosis

• Direct mechanism++.

• Localized painat the joint.

• Pronounced prominence of the lateral end of the clavicle.

• Digital pressure can reduce it temporarily, but it springs back: "Piano Key Sign".

• Sometimes mobile clavicle (antero-posterior):"Drawer Sign of the Clavicle".

Radiographic Diagnosis

• Loss of contact.

• Increased acromio-coracoid distance+++.

Classification

Treatment

• Orthopedic:

  • Strapping.

  • Bandaging.

• Surgical:

  • Direct suture.

  • Ligamentoplasty.

  • Screwing.

Sternoclavicular Luxation

Diagnosis

• Anterior Sternoclavicular Luxation:

  • Fall on shoulder + retropulsion.

  • Obvious deformity with prominence of medial clavicle end.

  • Pain++.

  • Radiography difficult (superimposition).

• Posterior Sternoclavicular Luxation:

  • Direct anterior impact or lateral chest compression with shoulder in antepulsion.

  • Less obvious.

  • Severity+++ (risk of compression of vital thoracic elements):

    • Aortic arch and pulmonary artery, superior vena cava.

    • Esophagus and trachea.