A shoulder dislocation occurs when the upper arm bone (humerus) slips out of its socket in the shoulder blade (glenoid). Because the shoulder joint is highly mobile and shallow, it is also one of the most unstable joints in the body, making it more prone to dislocation than other joints.

Dislocation can happen partially (subluxation) or completely, where the bone is entirely displaced from its socket. This often causes sudden pain, visible deformity and restricted arm movement. Without proper treatment and rehabilitation, recurrent dislocations may occur and lead to chronic instability or arthritis over time.

What are the types of Shoulder Dislocation?

Shoulder dislocations are classified based on the direction in which the upper arm bone moves out of its socket, such as:

• Anterior dislocation (most common) – the humeral head slips forward, usually after the arm is stretched or rotated outward. It accounts for nearly 95% of all shoulder dislocations. Common in contact sports (sports or overuse injuries page) or falls onto an outstretched hand, anterior dislocations can stretch or tear the ligaments at the front of the shoulder.

• Posterior dislocation – the humeral head moves backward, often due to a direct blow to the front of the shoulder or strong muscle contractions during seizures or electric shock. It is less common but can be easily missed without imaging, as symptoms may mimic rotator cuff injuries.

• Inferior dislocation (rare) – also known as luxatio erecta, this occurs when the humeral head is pushed downward below the socket. It often results from a sudden, forceful overhead movement. Patients may present with an arm stuck above the head and it is frequently associated with nerve or vascular injury.

• Multidirectional instability – this occurs when the shoulder repeatedly slips out of place in more than one direction. This may involve forward, backward or downward. It typically develops over time due to loose ligaments, repetitive overuse or previous dislocations, rather than a single traumatic event.

What causes Shoulder Dislocation?

Shoulder dislocation usually happens when excessive force is applied to the joint, pushing the humeral head out of its normal position. Some of the common causes include:

• Sports injuries – contact or high-impact sports such as rugby, basketball or volleyball often involve falls or collisions that stress the shoulder.

• Falls – landing on an outstretched arm or shoulder is one of the most frequent causes, especially among older adults.

• Sudden trauma – road accidents or a direct blow to the shoulder can easily dislodge the joint.

• Repetitive overhead motion – activities like swimming or throwing may gradually weaken stabilising structures, making dislocation more likely.

• Previous dislocation – once the shoulder has been dislocated, the surrounding ligaments and capsule become stretched or torn, predisposing it to repeat episodes.

What are the symptoms of Shoulder Dislocation?

The symptoms typically appear immediately after the joint is placed, with the common signs including:

• Inability to move the arm or shoulder
• Numbness, tingling or weakness down the arm. From nerve irritation or compression
• Severe pain that worsens with movement
• Swelling and bruising
• Visible deformity or bulging around the shoulder

If a dislocation is suspected, it is important not to force the joint back into place. Doing so may cause further damage to the nerves, blood vessels or surrounding tissues.

Who is at risk of Shoulder Dislocation?

The shoulder’s flexibility comes at the expense of stability, which increases the risk of dislocation. As such, some of the common contributing factors are:

• Age – those under 30 years old, particularly young active males, are more likely to sustain a traumatic shoulder dislocation.

• Loose or hypermobile joints – people with naturally flexible joints (joint laxity) are more prone to dislocations even with minimal force.

• Muscle weakness or imbalance – weak rotator cuff or scapular muscles may fail to stabilise the joint during movement, raising the risk of slippage.

• Sports participation – contact or overhead sports such as rugby, basketball, volleyball and swimming put the shoulder at risk due to sudden twisting or forceful impact.

• Trauma or falls – a fall onto an outstretched arm or a direct blow to the shoulder can push the humeral head out of its socket.

• Previous dislocation – once the shoulder has dislocated, the surrounding ligaments and capsule may become stretched or torn, increasing the risk of recurrence.

How is Shoulder Dislocation assessed in Singapore?

A proper diagnosis confirms the type and severity of the dislocation and identifies any associated injuries, such as fractures or nerve damage.

The diagnostic measures often consist of:

• Medical history – Dr James Tan will ask questions related to when or how the injury occurred, past shoulder dislocations or injuries, as well as the level of pain, weakness or numbness. This will give him a general idea of the severity of the dislocation.

• Physical examination – our doctor will then proceed to assess the shoulder for visible deformity, swelling or abnormal arm position. He will also evaluate the shoulder’s range of motion and joint stability, while inspecting tenderness over specific areas. The nerve and blood vessel function in the affected arm will also be assessed.

• Imaging tests – these give your doctor a clearer picture of the extent of the injury. X-rays can help confirm the direction of the dislocation and check for fractures, while an ultrasound or magnetic resonance imaging (MRI) may be done to evaluate soft tissue injuries, such as labral tears or rotator cuff damage.

How is Shoulder Dislocation treated in Singapore?

Treatment for shoulder dislocation focuses on restoring the joint’s normal position, relieving pain and preventing future instability. However, the exact approach depends on whether it is a first-time dislocation, recurrent dislocation or involves significant tissue damage.

Conservative treatments

• Rest and activity modification – immobilising the arm in a sling for one to three weeks allows soft tissues around the joint to heal. During this period, avoid overhead or heavy lifting activities that could stretch the capsule and ligaments.

• Medication – short courses of non-steroidal anti-inflammatory drugs (NSAIDs) can reduce pain and swelling following the initial reduction of the dislocated joint.

• Cold therapy – applying ice packs in the early stages helps minimise swelling and discomfort. As healing progresses, gentle heat can improve circulation and ease stiffness.

• Supportive aids – a shoulder brace or immobiliser may be recommended to stabilise the joint and prevent further dislocation while healing takes place.

Non-surgical interventions

• Physiotherapy – once pain subsides, a structured physiotherapy programme begins to restore shoulder movement and strength. Exercises target the rotator cuff and scapular stabilisers to enhance joint control and reduce the risk of recurrence.

• Injections – corticosteroid injections may help relieve persistent inflammation and pain following a dislocation. In select cases, platelet-rich plasma (PRP) can support the healing of soft tissue injuries associated with the dislocation.

Surgical treatments

• Arthroscopic stabilisation – a minimally invasive procedure performed through small incisions to repair torn labral tissue or ligaments that cause recurrent instability, such as Bankart or SLAP repairs.

• Open stabilisation surgery – used when the damage is extensive or previous arthroscopic repair has failed. It allows direct access for the reconstruction of ligaments and capsules.

• Bone augmentation procedures – in cases of bone loss from repeated dislocations, bone grafts may be used to restore shoulder stability and prevent future slippage.

• Shoulder replacement – reserved for severe cases involving irreparable bone or joint surface damage, typically in older patients with associated arthritis or fracture-dislocation.

Rehabilitation

• Targeted exercise programmes – gradual stretching and strengthening exercises restore range of motion and help stabilise the shoulder joint.

• Post-operative physiotherapy – following surgery, rehabilitation focuses on regaining strength and movement safely while protecting repaired tissues.

• Lifestyle advice – guidance on posture, sleeping position and safe techniques for lifting or returning to sports reduces the chance of reinjury.

Alternative therapies

• Massage therapy – gentle massage may ease muscle tension and improve circulation, especially during the later stages of recovery.

• Supplements and natural remedies – some individuals use glucosamine, collagen or turmeric to support joint health, though evidence for their effectiveness remains limited.

Book an Appointment

Shoulder dislocations can be painful and often signal underlying joint instability that should not be ignored. Early assessment and proper management are key to preventing long-term weakness or recurrent dislocations.

If you have experienced a dislocation or persistent shoulder pain after an injury, schedule a consultation with Dr James Tan, our orthopaedic specialist. He will perform a thorough examination, identify any ligament or soft-tissue injury and discuss the most suitable treatment plan for your recovery.

Prompt care not only reduces discomfort but also protects your shoulder from future complications. Book your appointment today to regain strength, confidence and full use of your shoulder.