Shoulder pain

The Acromioclavicular joint (ACJ)

An acromioclavicular (AC) joint injury refers to damage to the joint that connects the acromion (the top part of the shoulder blade) and the clavicle (collarbone). This joint plays a key role in shoulder movement, so when it's injured, it can significantly impact the function and mobility of the shoulder.

It’s. commonly injured during sporting activities, and can be as a result of trauma or overuse (such as throwing). AC joint injuries are typically classified into grades:

Grade I: A mild sprain of the AC joint where the ligaments are stretched but not torn. There might be some tenderness and swelling, but there’s no significant displacement of the bones.

Grade II: A partial tear of the ligaments that results in some displacement of the clavicle, leading to more noticeable pain, swelling, and bruising. Movement of the shoulder can become quite difficult.

Grade III: A complete tear of the ligaments that stabilise the joint, resulting in a more obvious separation between the acromion and clavicle. This can cause severe pain, swelling, bruising, and a visible bump above the shoulder.

Rotator cuff tear & tendinopathy

The ‘rotator cuff’ comprises the group of muscles and tendons that surround the shoulder joint. This group of muscles is crucial for stabilising the shoulder and allowing it to move freely in a range of directions. Tears of the cuff can be partial or complete, and are commonly caused by repetitive overhead motions (like throwing, lifting, or swimming) or by a sudden injury. Tendinopathy of the cuff can be acute (sudden) or chronic, building up gradually over a long period of time.

Common symptoms of a rotator pain:

  • Pain in the shoulder, especially when raising the arm or lifting objects.

  • Weakness in the shoulder.

  • Difficulty with overhead movements.

  • A feeling of instability or catching in the shoulder.

Labrum tear

The glenoid labrum is a piece of cartilage that forms a cup-like structure around the shoulder socket (glenoid). The labrum helps to stabilise the ball-and-socket joint by deepening the socket and providing a surface for the shoulder’s ball (humerus) to move smoothly within. A tear in this cartilage can lead to pain, instability, and limited movement in the shoulder. Labral tears can occur through overuse injury (a SLAP tear) or due to trauma such as a dislocation of he shoulder (resulting in a Banakart lesion).

Common symptoms of a labrum injury:

  • Shoulder pain, especially when lifting the arm or reaching behind the back.

  • Clicking, popping, or grinding sensations during movement.

  • Instability or weakness in the shoulder.

  • Limited range of motion or a feeling of the shoulder "giving way."

Subacromial impingement

Subacromial impingement is a common shoulder condition where the supraspinatus tendon becomes compressed or pinched between the acromion (the bony part of the shoulder blade that forms the top of the shoulder) and the humeral head (the ball of the upper arm bone). This compression typically occurs when the arm is lifted, leading to pain, inflammation, and sometimes weakness in the shoulder.

Common symptoms:

  • Pain in the shoulder when lifting the arm above the head.

  • Pain in the front or outer part of the shoulder.

  • Weakness in the shoulder, particularly when trying to lift the arm.

  • Limited range of motion, particularly in overhead movements.

  • Night pain, especially if lying on the affected side.

Posterior capsule impingement

The posterior capsule helps to stabilise the shoulder joint and prevent excessive movement, but if it becomes inflamed or irritated, it can lead to impingement. This condition is less common than anterior (front) shoulder impingement but can still be quite problematic, especially for athletes who perform repetitive overhead activities like swimming, tennis, or weightlifting. This condition can be caused by a number of issues but is particularly common with repetitive overuse, and shoulder instability due to previous injury.

Common symptoms:

  • Pain at the back of the shoulder, especially when moving the arm overhead or behind the back.

  • Weakness in shoulder movements that require stability and control.

  • Discomfort during certain activities, like reaching back to put a seat belt on.

  • Pain while sleeping, especially when lying on the affected shoulder.

Frozen shoulder

Frozen shoulder, also known as adhesive capsulitis, is a condition characterised by pain and stiffness in the shoulder joint that progressively limits movement. The condition develops when the shoulder capsule (the connective tissue surrounding the joint) becomes inflamed and thickened, causing the joint to tighten. Over time, the shoulder can become "frozen," and movement becomes very restricted. There are a number of known triggers of risk factors for frozen shoulder; iatrogenic (triggered by a surgery for another condition), people with diabetes have a greater risk, age (more common between 40 and 60 years old).

1. Freezing Stage (Painful Stage)

  • This stage can last anywhere from 6 weeks to 9 months.

  • Symptoms: Pain starts to develop in the shoulder, often worsening with movement, particularly at night. The shoulder becomes progressively stiffer, making it difficult to raise the arm or reach overhead.

  • Pain: The pain is often described as a dull ache, but it can become sharper with specific movements.

2. Frozen Stage (Stiffening Stage)

  • This stage can last 4 to 6 months.

  • Symptoms: The pain may begin to subside, but the shoulder becomes increasingly stiff, and the range of motion is significantly reduced. Simple daily tasks, such as reaching behind the back or lifting the arm, become difficult or impossible.

3. Thawing Stage (Recovery Stage)

  • This stage typically lasts 6 months to 2 years.

  • Symptoms: Gradual improvement in the range of motion and reduction in stiffness occurs. The shoulder begins to recover, but full recovery can take a while.

Shoulder dislocation

The shoulder joint is a ball-and-socket joint, and it’s the most mobile joint in the body. However, because of its range of motion, it is also prone to dislocations, especially if the joint is subjected to significant trauma or force. Anterior dislocation is by far the most common and accounts for around 95% of all cases. The humeral head moves forward out of the socket, typically caused by a force that pushes the shoulder backward - falling on an outstretched hand or direct impact to the shoulder is a common mechanism.

Signs and symptoms:

Severe pain in the shoulder, usually instantly after the injury.

Obvious deformity - the shoulder may appear out of place, and the arm is often dropped down and turned in towards the body in a protective guard.

Severe pain with movement - you won’t be able to move the shoulder normally, and any attempt to do so will likely cause extreme pain.