Shoulder Dislocations in Rugby League: First Time, Last Time?

Apr 29

The shoulder goes forward. The arm flies out on a tackle and the head of the humerus pops out the front of the joint. It’s one of the most dramatic injuries on a rugby league field, and also one of the most predictable in terms of what comes next.

Because the first dislocation predicts the second. And the second predicts the third.

The Anatomy of Instability

The shoulder joint is a ball and socket, but the socket is shallow, more like a plate than a cup. The glenoid labrum, a ring of fibrocartilage that deepens the socket, provides a significant portion of the joint’s passive stability. The anterior inferior labrum, the part at the front and bottom of the socket, bears the greatest load during a dislocation.

When the shoulder dislocates anteriorly (forward), which accounts for 95% of traumatic dislocations, the labrum is torn off the glenoid rim. This is called a Bankart lesion. Alongside this, the inferior glenohumeral ligament, the primary restraint to anterior translation of the shoulder, is stretched or ruptured.

The result is a joint that has lost its structural restraint to the same mechanism that caused the dislocation in the first place. Without surgical repair, the recurrence rate in young, active males in contact sport is above 80%.

How It Happens in Rugby League

Tackles are the primary mechanism. The arm is forced into abduction (up and out) and external rotation, which is the position of maximum anterior instability. Direct hits to the outstretched arm in a tackle, falling on an outstretched hand, and impact during a ball carry all produce the same anterior translation of the humeral head.

Halves and five-eighths carry the ball frequently with the arm in exposed positions. Props and forwards sustain dislocations from contact during tackling and wrestling in the ruck.

On-Field Management

A dislocated shoulder should be reduced by a qualified practitioner as soon as safely possible. Do not attempt reduction on the field without the right training. Neurovascular assessment, which checks sensation and circulation in the arm, must precede any reduction attempt.

After reduction, sling immobilisation for comfort and urgent imaging to assess for bony Bankart (fracture of the glenoid rim) and Hill-Sachs lesion (dent in the humeral head from impact).

Surgical vs. Conservative Management

For a first-time dislocation in a competitive rugby league player under 25, the evidence strongly favours surgical stabilisation. Conservative management in this population has a 75-90% re-dislocation rate. That’s not a management option, it’s a delay.

For older players or those with significant comorbidities, conservative management with structured rehabilitation has a reasonable case, particularly for older players with lower instability demands.

Rehab Post-Surgery

Surgical stabilisation (arthroscopic Bankart repair) has excellent outcomes in contact sport athletes.

Phase 1 (0-6 weeks): Sling immobilisation, pendulum exercises, grip and wrist movement. Phase 2 (6-12 weeks):Progressive range of motion, rotator cuff activation, scapular control. Phase 3 (3-5 months): Strength and load progression, sport-specific pressing and pulling. Phase 4 (5-6 months): Return-to-contact protocols, tackling technique, clearance testing.

Return to full contact competition averages 6 months post-surgery. Return to pre-injury performance standards often takes 9-12 months.

Prevention

Rotator cuff and scapular stabiliser strengthening significantly reduces shoulder injury risk in contact athletes. External rotation strength relative to internal rotation, the ER/IR ratio, should be above 0.75 in rugby league players. Most are well below this.

Systematic shoulder screening pre-season, addressing this ratio and posterior capsule tightness, is one of the most cost-effective injury prevention investments a rugby league club can make.

Want to understand this injury at a deeper anatomical level? The Club Physio’s online anatomy course breaks down the structures, biomechanics, and load patterns behind the most common sports injuries. Built for athletes and therapists alike. [Explore the course at theclubphysio.com.au]

josh zoppo