Mr. Nnamdi Obi Specialist registrar United Kingdom Anatomy, diagnosis and classification of sports injuries in the shoulder Mr. Nnamdi Obi Specialist registrar United Kingdom

Objectives Review anatomy of the shoulder Review history and examination Acute traumatic shoulder instability

Introduction Instability Glenohumeral dislocation ACJ dislocation SLAP tears ACJ dislocation

30 YO male,Professional Rugby payer, first episode

Anatomy Synovial ball and socket joint Articular surface covered with hyaline cartilage Glenoid cavity deepened by labrum Articulations

Rotator cuff Supraspinatus Infraspinatus Teres Minor Subscapularis

Ligaments Glenohumeral Shoulder girdle Superior Glenohumeral ligament Middle Glenohumeral Ligament Inferior Glenohumeral Ligament Shoulder girdle Coraco clavicular ACJ proper Acromioclavicular

Biomechanics Static restraints Dynamic restraints Glenoid labrum Articular version + conformity Glenohumeral ligaments Negative intra-articular pressure Rotator cuff muscles Biceps tendon Scapular stabilizers Neuromuscular factors

History (Acute traumatic instability) Age Mechanism Traumatic Atraumatic Chronicity Ease of dislocation Expectations Return to play

Examination Acutely Delayed Pain limits most Pre and post axillary nerve function Sensory Motor Delayed Hyperlaxity – predisposing Provocative tests Labral pathology (SLAP tear)

Sulcus sign

Apprehension

Relocation test

Labrum (SLAP) O’Brien’s

Labrum Load & Shift

Special investigations Bones Glenoid Head humerus Soft tissues Rotator cuff Labrum X Ray CT scan Ultrasound – no labrum MRI CT arthrogram MRI arthrogram

Lateral radiographs Posterior oblique scapular projection (“Neer lateral”, Neer 1970) Produces considerable image overlap Transthoracic (Vastamaki and Solonen 1980) Image overlap Axial (Warrick 1965) Requires shoulder abduction Modified axial (Rockwood 1984) Some shoulder abduction Velpeau lateral (Wallace and Hellier 1983) Patient needs to sit up Apical oblique (Garth, Slappey and Ochs 1984)

This is posterior dislocation But outlines glenoid and humeral head J Bone Joint Surg [Br] l988;70-B:457-60.

Axial view Small Hills sachs Anterior glenoid Fine Almost normal AP Same patient Apical oblique Large Hills sachs Blunting anterior glenoid

Bone loss - Plain x-ray - CT - CT recon

30 YO male, football, first episode

Treatment How long ?

MRI study Randomized 40 pts IR Labrum off glenoid ER tension rests on glenoid Randomized 40 pts Sling IR Vs ER Recurrence IR 6/20, 30% ER 0/20 J Shoulder Elbow Surg 2003;12: 413-15

JBJS – B VOL. 91-B, No. 7, JULY 2009

Premise Younger = recurrent instability = immobilize longer Older = stiffness = mobilize sooner No benefit to immobilization in internal rotation > 1 week in pts under 30 yrs of age Age of less than thirty years at time of injury predicts increased recurrence. Best available evidence does show a clinical benefit to treatment in external rotation over conventional sling immobilization, but this advantage did not reach significance BUT most ITOI J Bone Joint Surg Am. 2010;92:2924-33

Take Home Reduce Sling comfort Under 30 years, continue contact sport Discard in 1 week Physiotherapy, strengthen dynamic stabilizers Under 30 years, continue contact sport Counsel recurrence rate Consider surgery following first dislocation

SLAP Lesions May be associated with dislocation but commonly due to pull on the arm, weightlifting, throwing, tackling Symptoms – clicking, pain with overhead activities Clinically – pain with eccentric biceps loading (e.g. going down on bench press)

SLAP lesion classification

Acromioclavicular joint (ACJ) injuries Usually injured by a direct fall onto the point of the shoulder Scapular forced downwards Clinically, lateral end of clavicle prominent

30 YO rugby player again

Classification of ACJ Injuries (Rockwood) Anatomy diathrodial joint · has fibrocartilage intraarticular disc · Usually degenerative by 4th decade · Clavicle may lie superior normally- See more at: http://www.orthofracs.com/adult/trauma/shoulder/acj-dislocation/anatomy.html#sthash.iqMghqCm.dpuf   Stability of ACJ Coracoacromial ligaments Primary restraint to superior translation Primary suspensory ligament of upper limb Trapezoid Ligament Arises anterolateral on coracoid Inserts trapezoid ridge anterolateral to conoid Almost horizontal in sagittal plane PRIMARY restraint to AXIAL compression Conoid Ligament Arises posteromedial to trapezoid Inverted cone Inserts conoid tubercle Lies vertically PRIMARY restraint to SUPERIOR & Anterior translation ACJ Capsule Strongest superiorly As reinforced by acromioclavicular ligament (strongest superiorly) Has incomplete fibrocartilage intra-articular disc arising from it Usually degenerates by 4th decade Deltotrapezial Fascia Dynamic stabiliser -

Treatment Non Operative Grade 1-3 Operative Grade 4-6

Conclusions Acute instability common in athletes Glenohumeral ACJ High level of function Early return to play Axillary or modified axillary view Apical oblique

References Websites: https://www.shoulderdoc.co.uk https://www.orthobullets.com

The End Email: njco@hotmail.com