What is a shoulder dislocation?
A dislocation is when the ball of the upper arm bone, the humeral head, is forced completely out of its socket on the shoulder blade. That is different from a subluxation, where it partly slides out and goes back on its own. The shoulder is built unstable on purpose. The socket is shallow, often described as a golf ball on a tee, and that shallowness is what buys you the range of motion you need to throw, reach, and tackle. What holds it together is soft tissue: the labrum, a cartilage rim that deepens the socket, the ligaments thickening the joint capsule, the rotator cuff, and the muscle around it.
When the humeral head is forced out of the socket, these stabilising structures are torn or stretched. The direction the ball goes determines the type of dislocation and the structures damaged.
Types of shoulder dislocation
| Type | Direction | Frequency in rugby | Typical mechanism |
|---|---|---|---|
| Anterior dislocation | The humeral head moves forward (in front of the socket) | The great majority of rugby dislocations | The arm forced into abduction and external rotation, which is the classic tackle position with the arm pulled backward and outward |
| Posterior dislocation | The humeral head moves backward (behind the socket) | Uncommon | A direct blow to the front of the shoulder, or falling forward onto an outstretched hand with the arm rotated inward |
| Inferior dislocation (luxatio erecta) | The humeral head moves downward below the socket | Rare | A severe hyperabduction force, and very uncommon in rugby |
How dislocations happen in rugby
- Tackle contact is the most common mechanism. The tackling arm is forced into abduction and external rotation as the ball carrier drives through, levering the arm away from the body and pushing the humeral head out of the front of the socket.
- A fall on an outstretched arm, landing with it extended and out to the side, reaching to score or bracing as you go down. The force travels up the arm and levers the head out of the socket.
- Ruck and maul contact, with arms trapped in awkward positions at the breakdown while other players load the extended limb.
- A direct blow to the shoulder. A forceful hit from behind or from the side can drive the humeral head forward, particularly if the shoulder muscles are not braced.
What happens on the field
When a shoulder dislocates the player gets immediate, severe pain and cannot move the arm. The shoulder looks wrong. The rounded contour of the deltoid is gone and there may be a visible step or hollow where the head has moved. The player will instinctively hold the injured arm with the other hand, and in an anterior dislocation the arm sits slightly away from the body and will not move.
What else gets damaged
A dislocation is rarely a simple pop out and pop back in. The force needed to take the joint apart nearly always damages what surrounds it, and the pattern of that damage is what decides the prognosis and whether surgery comes into it.
| Injury | What it is | How it affects recovery |
|---|---|---|
| Bankart lesion | A tear of the labrum at the front and bottom of the socket, and the usual finding after an anterior dislocation. | This is the main reason a shoulder becomes recurrently unstable. The torn labrum no longer deepens the socket or anchors the ligament below it, so without repair the shoulder stays vulnerable. |
| Hill-Sachs lesion | A compression fracture, effectively a dent, in the back and outer part of the humeral head, made as it hits the rim of the socket on the way out. | Small ones are common and generally well tolerated. A large, engaging lesion, where the dent catches on the rim as the arm moves, adds a lot of instability and often needs addressing surgically. |
| Rotator cuff tear | Tearing of one or more rotator cuff tendons during the dislocation. More likely in older players, but it happens at every age. | May require separate surgical repair. Significantly slows rehabilitation and affects overhead function. |
| Axillary nerve injury | A stretch injury to the axillary nerve as the head displaces. The nerve wraps around the neck of the humerus. | Causes numbness over the outer deltoid, the regimental badge area, and weakness in the deltoid. Most are temporary and recover over 6 to 12 weeks. It has to be checked after the shoulder is reduced. |
| Greater tuberosity fracture | A fracture of the bony prominence where the rotator cuff attaches to the humerus. It often pulls off during the dislocation. | If the fragment has barely moved it may heal without surgery, pulled back into place as the shoulder is reduced. A significantly displaced fragment needs fixing. |
Age and recurrence
Age is the strongest single predictor of whether a shoulder goes again after a first dislocation. Younger players have more elastic tissue and are more likely to have a significant labral tear, and both push towards it happening again. That changes the management. In a 17-year-old with a first anterior dislocation, recurrence on rehab alone is likely enough that many surgeons now recommend stabilising it early rather than waiting for the next one. A first dislocation at 35 is a different conversation, and conservative management with surgery held in reserve is often the right call.
Conservative vs surgical management
Whether you go conservative or surgical depends on several things. Your orthopaedic surgeon will weigh your age, the sport and position you play, how much structural damage there is, and what you want out of the next few years. What follows is a rough guide to how that conversation usually goes.
| Factor | Favours conservative management | Favours surgical stabilisation |
|---|---|---|
| Age | Over 30, where conservative treatment more often holds | Under 25, where recurrence is likely enough that early surgery is increasingly recommended |
| Demand level | Recreational athlete or willing to modify activity level | Competitive contact sport athlete who needs full confidence in the shoulder |
| Structural damage | Minimal labral tear, no significant bone loss, no engaging Hill-Sachs | A large labral tear, significant bone loss at the socket, or an engaging Hill-Sachs lesion |
| Episode | A first dislocation with a low recurrence risk profile | Recurrent dislocations or subluxations, where the instability is already established |
| Timing | Off-season surgery is impractical or the player is retiring soon | Off-season window available for surgery and rehabilitation (4–6 months required) |
How the rehab runs
Protection and early motion
0–3 weeks (conservative) / 0–6 weeks (post-surgery)
Sling immobilisation. Gentle pendulum exercises, and elbow, wrist, and hand movement so nothing else stiffens up. Ice for pain and swelling. The point is protecting what is healing while avoiding the secondary problems, which are a frozen shoulder and muscle wasting.
Getting the range back
3–6 weeks (conservative) / 6–12 weeks (post-surgery)
Range of motion work, starting passive with the physio or your other arm doing the moving, then active-assisted, then fully active. External rotation gets the most care because it loads the structures at the front that were injured. Isometric rotator cuff work starts here.
Strengthening
6–12 weeks (conservative) / 12–20 weeks (post-surgery)
Progressive rotator cuff and scapular work through full range. Closed chain first, push-ups on a stable surface and then an unstable one, then open chain with bands and light dumbbells. Core and trunk work underneath all of it.
Sport-specific preparation
12–16 weeks (conservative) / 20–28 weeks (post-surgery)
Rugby-specific work. Falling and landing on the shoulder, built up gradually. Contact on shields, grappling. Plyometrics for the shoulder, meaning medicine ball throws and drop catches. Full gym programme, overhead pressing included once you are cleared for it.
Back to full contact
16–20 weeks (conservative) / 24–32 weeks (post-surgery)
Full contact training, then match play. You need full range, strength matching the other side, confidence in contact, and to pass sport-specific testing. Taping or bracing is common through the return and often stays on for the rest of the season.
Bracing and taping for return to play
Most players coming back from a dislocation use some external support through the return phase, and often for the rest of the season. A shoulder brace limits external rotation, the position where the joint is most vulnerable, while leaving you able to play. Rigid taping does a similar job, applied by a physio before each match to limit end-range abduction and external rotation. Kinesiology tape gives you proprioceptive feedback rather than mechanical restriction, so it may help your awareness of where the arm is but it will not hold the joint in. None of it removes the risk. An unrepaired labral tear is still an unrepaired labral tear whatever is taped over it.