Shoulder Dislocations and Anatomy

Joints Dislocation

• Joints dislocation is a common injury, particularly the shoulder.
• Shoulder dislocation is frequent due to the shallow glenoid socket and wide range of movement.
• Types of shoulder dislocation include anterior, posterior, and inferior.
• Anterior dislocation is the most common type, often resulting from a fall or excessive abduction and external rotation.
• Posterior dislocation is rare, often associated with internal rotation forces.
• Inferior dislocation is also rare.

Shoulder Anatomy

• Shoulder stability relies on soft tissues, not inherent bony structure.
• The rotator cuff is a dynamic stabilizer, using muscle tension and compression.
• The glenohumeral ligament (GHL) and capsule are static stabilizers, providing ligament tightening.
• Glenoid bone stock is limited.

Shoulder Dislocation Classification

• TUBS: Traumatic, unidirectional, Bankart lesion, surgery required.
• AMBRI: Atraumatic, multidirectional, bilateral, rehabilitation is the primary treatment, sometimes requiring inferior capsular shift surgery.
• Traumatic dislocations are further categorized as anterior, posterior, and multidirectional.

Shoulder Dislocation Pathology

• Traumatic anterior dislocation involves avulsion of the glenoid labrum and capsule, stretching of the capsule, and indentation of the posterolateral humeral head.

Causes of Shoulder Dislocation

• Sports injuries (e.g., football, rugby, hockey, skiing)
• Accidents (e.g., traffic accidents)
• Falling on the shoulder or outstretched arm
• Seizures and electric shocks

Shoulder Dislocation Risk Factors

• Previous shoulder dislocations (80-90% incidence)
• High-risk sports (contact sports like football, rugby, hockey, skiing)
• Congenital conditions (like Ehlers-Danlos Syndrome)
• Weakness of shoulder and core muscles
• Incorrect posture and inadequate training technique

Shoulder Dislocation Signs and Symptoms

• Severe shoulder pain
• Swelling and bruising of the shoulder or upper arm
• Numbness or weakness in the arm, hand, or fingers
• Trouble moving the arm
• Feeling the arm being out of place
• Muscle spasms in the shoulder

Shoulder Dislocation Clinical Picture

• Injured limb held close to the trunk with the elbow flexed.
• Loss of normal shoulder contour
• Anterior bulge of the humeral head might be noticeable and palpable

Radiology and MRI

• X-rays and MRI scans are used in diagnosis to assess injury severity and associated fractures.
• Radiology examines the bone structure for any dislocation or associated fractures.
• MRI examines the soft tissues to identify any tears in the rotator cuff, capsule, or glenoid labrum.

Shoulder Dislocation Treatment

• Non-operative treatment (closed reduction) is usually the initial approach, often performed under anesthesia. It involves manually repositioning the humeral head.
• Post-reduction, immobilisation is important for healing, along with ice/heat and/or non-steroidal anti-inflammatory drugs (NSAIDs).
• Physiotherapy is crucial for restoring range of motion and strengthening the shoulder muscles, after the initial recovery period.
• Surgical treatment is indicated for old or recurrent dislocations or if non-operative methods fail.
• Surgical techniques include open or arthroscopic procedures.

Shoulder Dislocation Prevention

• Taking care and avoiding falls.
• Wearing protective gear in contact sports.
• Regular exercise to maintain strength and flexibility in shoulder joints and muscles.

Elbow Dislocation

• Elbow dislocation is a common injury in children and young adults, with posterior dislocation being the most frequent.
• This is mostly caused by falls on an outstretched hand.
• Ligaments and capsule of the elbow are damaged during dislocation.
• The medial and lateral collateral ligaments, along with the anterior capsule are affected.

Elbow Dislocation Treatment

• Urgent closed reduction under general anesthesia, using gradual gentle longitudinal traction to reposition the bones.
• The hand of the surgeon manipulates the radius and ulna and moves them into their normal position.
• The elbow is immobilized for several weeks in a cast.
• Rehabilitation, including gentle exercises and range of motion activities, will start soon after to avoid myositis ossificans and stiffness.

Wrist Dislocation

• Lunate dislocation is common in wrist dislocations.
• It may lead to carpal tunnel syndrome (CTS).
• Open reduction is sometimes needed for lunate dislocations.
• Hand rehabilitation is important for maintaining hand function and preventing stiffness.