Dislocated Shoulder: Movement Limitations, Causes, and What to Do

Can you move your arm with a dislocated shoulder?

No, you generally cannot move your arm with a dislocated shoulder due to extreme pain, significant instability, and involuntary muscle spasm that locks the joint in place.

Understanding Shoulder Dislocation

A shoulder dislocation occurs when the head of the humerus (the ball of the upper arm bone) is forced out of the glenoid fossa (the shallow socket of the shoulder blade). This is a severe injury to the glenohumeral joint, which is the most mobile joint in the human body, allowing for a wide range of motion. Its mobility, however, comes at the cost of stability, making it prone to dislocation. Most dislocations are anterior (forward), but they can also be posterior (backward) or inferior (downward).

The Immediate Aftermath: Movement Limitations

Upon dislocating your shoulder, the ability to move your arm is severely compromised, if not entirely eliminated. This inability stems from a combination of factors:

• Excruciating Pain: The primary sensation is intense, sharp pain as the bones separate and surrounding tissues are stretched or torn. This pain alone makes any voluntary movement virtually impossible.
• Gross Instability and Deformity: The joint is no longer properly aligned. You may visibly notice a deformity, such as a bump under the skin (the humeral head) or a flattened appearance of the shoulder where the deltoid muscle normally rounds it out. Attempting to move the arm will only exacerbate this instability.
• Involuntary Muscle Spasm (Guarding): The muscles surrounding the shoulder joint, particularly the rotator cuff and deltoid, will immediately go into severe spasm. This is an involuntary protective mechanism by the body, attempting to stabilize the joint and prevent further damage. This spasm effectively "locks" the arm in a painful, often awkward, position, making conscious movement impossible.
• Potential Nerve and Blood Vessel Involvement: In some cases, a dislocated shoulder can also stretch or compress nerves (like the axillary nerve) or blood vessels. If nerve damage occurs, it can directly impair muscle function and sensation in the arm and hand, further preventing movement.

Why Movement Is Severely Restricted (Biomechanics & Anatomy)

The inability to move the arm with a dislocated shoulder is a direct consequence of the anatomical disruption and the body's protective responses:

• Loss of Articulation: The very definition of a dislocation means the joint surfaces are no longer in contact. For the shoulder, the humeral head is no longer articulating within the glenoid fossa. Without this proper mechanical connection, the leverage needed to move the arm through its normal range of motion is lost.
• Capsular and Ligamentous Damage: The fibrous joint capsule and the strong ligaments (e.g., glenohumeral ligaments) that normally hold the humerus within the glenoid are stretched, torn, or avulsed (pulled away from the bone). These structures are crucial for joint stability, and their compromise renders the joint mechanically unstable.
• Rotator Cuff Strain/Tear: The four muscles of the rotator cuff (supraspinatus, infraspinatus, teres minor, subscapularis) are responsible for stabilizing the shoulder and initiating many arm movements. A dislocation can severely stretch or even tear these muscles or their tendons, further contributing to pain and inability to move.

What to Do If You Suspect a Dislocation

If you or someone else suspects a shoulder dislocation, immediate and appropriate action is critical to prevent further injury:

• Do NOT Attempt to Relocate the Shoulder: Never try to "pop" the shoulder back into place yourself. This can cause severe damage to nerves, blood vessels, ligaments, cartilage, or the bone itself. Only a trained medical professional should perform this procedure.
• Immobilize the Arm: Support the arm in the most comfortable position possible. This often means holding it close to the body. A sling, a pillow, or even just holding the arm still with the other hand can help.
• Seek Immediate Medical Attention: A dislocated shoulder is a medical emergency. Go to the nearest emergency room or call for an ambulance immediately. Medical professionals can confirm the diagnosis with X-rays, assess for complications, and safely perform a reduction (re-aligning the joint).
• Apply Ice (Carefully): If possible and without causing more pain, apply ice packs to the affected area to help reduce swelling and pain while awaiting medical attention.

The Road to Recovery: Post-Reduction Movement

Once a medical professional has successfully reduced (re-aligned) the dislocated shoulder, movement will still be restricted initially:

• Initial Immobilization: After reduction, the shoulder will typically be immobilized in a sling for a period (e.g., 2-4 weeks) to allow damaged tissues to begin healing. During this time, only very limited, controlled movements may be advised, if any.
• Rehabilitation: A structured rehabilitation program, guided by a physical therapist, is essential. This program will gradually reintroduce movement, starting with passive range of motion, progressing to active-assisted, and then active range of motion exercises. Strengthening exercises for the rotator cuff and periscapular muscles will follow to restore stability and function.
• Gradual Return to Activity: The return to full activity, especially sports or overhead movements, is a gradual process that can take several months. Rushing this process increases the risk of re-dislocation.

Key Takeaways

A dislocated shoulder is a significant injury that renders the arm effectively immobile due to pain, instability, muscle spasm, and anatomical disruption. Attempting to move it or self-reduce it can lead to severe complications. Immediate medical attention is crucial for proper diagnosis, safe reduction, and a structured rehabilitation plan to restore function and minimize the risk of future dislocations.