What is shoulder instability?
Shoulder instability is a condition in which the shoulder joint is unable to maintain the head of the upper arm bone securely within the shallow socket of the shoulder blade, leading to excessive movement or slipping of the joint. Because the shoulder is the most mobile joint in the body, it relies heavily on soft tissues such as ligaments, the joint capsule, and surrounding muscles for stability. When these structures are stretched, weakened, or injured—often due to trauma, repetitive strain, or congenital laxity—the joint can become unstable. This may result in partial displacement (subluxation) or complete dislocation, causing pain, weakness, and a feeling that the shoulder may “give way” during certain movements.
Causes
A common cause is traumatic injury, such as a fall or collision, which can lead to dislocation and stretching or tearing of the ligaments and joint capsule. Repetitive overhead activities—seen in sports like swimming, tennis, or throwing—can gradually loosen these stabilising tissues over time, leading to instability without a single major injury. Some individuals also have naturally loose ligaments (joint laxity), making them more prone to instability even with minimal strain. In addition, poor muscle control or weakness in the rotator cuff and scapular muscles can reduce dynamic stability, increasing the risk of the shoulder slipping out of place.
Symptoms
- Feeling of looseness or “giving way”: A sensation that the shoulder may slip out of place, especially during certain movements or positions
- Recurrent dislocations or subluxations: The shoulder may partially (subluxation) or fully dislocate repeatedly due to weakened stabilising structures
- Shoulder pain: Ongoing or intermittent pain, often worsened by activity or specific arm positions that stress the joint
- Apprehension with movement: Fear or hesitation when moving the arm, particularly overhead or outward, due to the risk of dislocation
- Weakness: Reduced strength in the shoulder muscles, often from disuse or inability to generate force safely
- Clicking or catching sensation: Abnormal joint movement can cause noticeable clicking, popping, or catching during motion
- Reduced range of motion: Movement may be limited either by pain or by the individual consciously restricting motion to avoid instability
Diagnosis
Your surgeon diagnoses shoulder instability through a combination of detailed history-taking, physical examination, and imaging studies.
The process begins by discussing the patient’s symptoms, including any history of dislocations, trauma, or sensations of the shoulder “giving way.”
During the physical examination, the surgeon assesses range of motion, strength, and performs specific instability tests—such as the apprehension and relocation tests—to evaluate how easily the joint moves out of place.
Imaging
Imaging techniques are then used to confirm the diagnosis and identify underlying damage; X-rays can reveal bone abnormalities or previous dislocations, while MRI scans provide detailed views of soft tissues like the labrum, ligaments, and rotator cuff. In some cases, CT scans may be used to assess bone loss or structural changes, helping guide appropriate treatment planning.
Treatment
Conservative (non-operative)
Focuses on improving joint stability, reducing symptoms, and preventing further episodes of dislocation. This typically involves a structured physiotherapy program aimed at strengthening the rotator cuff and scapular stabilising muscles, which help keep the shoulder joint properly aligned during movement. Exercises also target proprioception (joint awareness) and neuromuscular control to enhance coordination and reduce the risk of the shoulder slipping out of place. Activity modification is often recommended, particularly avoiding positions or movements that provoke instability, such as overhead or externally rotated positions.
Surgical treatment
Is considered when conservative management fails or when there are repeated dislocations that significantly affect function and quality of life. It is commonly recommended after recurrent anterior shoulder dislocations or repeated subluxations, especially in younger and physically active individuals. Surgery is also indicated when imaging confirms structural damage such as a torn labrum or stretched ligaments that are unlikely to heal sufficiently with rehabilitation alone. In cases where instability interferes with sport, work, or daily activities—or when there is a high risk of further dislocations due to contact sports or overhead athletic demands—arthroscopic stabilisation is often advised to restore joint stability and reduce the likelihood of future injury.
The most common procedure is an arthroscopic stabilisation where the torn labrum and stretched ligaments are reattached to the front of the shoulder socket to restore stability. In cases with significant bone loss or recurrent instability, procedures like a Latarjet procedure may be performed to transfer a small piece of bone with an attached tendon to reinforce the front of the joint and prevent dislocation. Surgery aims to restore the normal anatomy and improve joint stability, followed by a carefully structured rehabilitation program to regain range of motion, strength, and safe return to activity.
Recovery
When can I return to daily activities?
This depends on the activity, the exact nature of your surgery and your progress with your rehabilitation.
Most people can:
- Return to office or light duties (no use of the arm at chest height or above, no repetitive duties, no heavy lifting) at 10-14 days. Sling should be worn when using a computer / doing admin work
- Walking for exercise from 3 weeks
- Driving – approximately 4-6 weeks, 15-30 minutes as you feel safe and confident. When you are no longer using the sling and have full control of the vehicle. No truck driving until 4 months
When can I participate in leisure activities?
Your ability to start these will be dependent on the range of movement and strength that you have in your shoulder following the operation. Please discuss activities in which you may be interested with your physiotherapist or surgeon. Start with short sessions, involving little effort and gradually increase.
General examples are:
- Cycling – 4 to 6 weeks
- Jogging – 12 weeks
- Swimming – gentle breast-stroke 12 weeks, freestyle variable timeframe (minimum 4 months)
- Light sports/racquet sports using non-operated arm – 10 weeks
- Racquet sports using operated arm – 4 months
- Contact or collision sports which includes horse riding, soccer, martial arts, football and rock climbing – 6 to 9 months