Why is Shoulder Pain Worse at Night?

Most people are able to engage in various positions while sleeping without much thought. However, sometimes people experience shoulder pain at night that for the most part, disappears during the day. This may be an indication they are beginning to experience some type of issue within the shoulder region. Anyone experiencing persistent shoulder pain while sleeping should seek medical attention in order to determine the exact cause of their pain.

Anatomy of the Shoulder

The shoulder joint is a ball and socket joint, where the rounded edge of the humerus (upper arm bone) fits within a shallow depression (glenoid fossa) located on the scapula, otherwise known as the shoulder blade.  The rotator cuff is a series of muscles and tendons that surround and support this area, as well as allowing movement of the arm and shoulder. The tendons of the rotator cuff are surrounded by a series of small sacs called bursa. These fluid-filled sacs provide protection and cushioning around the shoulder tendons. Sometimes these sacs or the rotator cuff tendons become inflamed and painful. In some cases, a tear occurs in a muscle or tendon that is part of the rotator cuff, and this is known as a rotator cuff tear.

Shoulder Injuries and Sleeping

People with underlying shoulder issues such as tendonitis, bursitis, or a rotator cuff tear will likely find it much more challenging to find a comfortable sleeping position, especially if they prefer to sleep on their affected shoulder.  Sleeping for hours on an injured shoulder compresses inflamed tissues, causing pain from the undue pressure. Depending upon the nature and severity of the issue, individuals may experience stiffness upon waking in the morning, a dull achy pain, numbness and/or tingling throughout the shoulder and arm area, or perhaps sharp pains radiating from the shoulder. In the initial stages of the injury, an individual may experience only pain at night which disappears during the day, leading them to believe their pain is caused by a poor-fitting pillow or mattress.  As the injury advances, some patients will start to feel shoulder pain even though they stopped sleeping on the affected shoulder.

A Diagnosis

The first step to resolve persistent shoulder pain at night is to obtain a proper diagnosis. In most cases, a physician will not suggest surgery. Instead, they will likely prescribe physical therapy as part of their first line of treatment. Depending upon the nature of the injury, a physical therapist will likely begin with pain-reducing measures such as ultrasound and gentle stretching exercises, along with suggestions on which movements and positions to avoid, both during the day and while sleeping in order to reduce pain.

Initially, many patients will find that simply sleeping on their opposite side or on their back during the recovery period will completely eliminate or reduce their pain during sleep. Depending upon the injury and the level of severity, a physical therapist may suggest the patient place a towel or a thin to medium-sized pillow underneath their affected arm and shoulder arm in order to provide cushioning and support. During the day, a patient may wear a lightweight sling over each shoulder to help promote proper posture while walking and moving about, as practicing good posture helps relieve pressure on tissues so they can heal faster.

As a patient’s injury improves, a physical therapist will introduce exercises designed to restore full range of motion, followed by strengthening exercises to improve muscle strength so the shoulder joint and surrounding tissues can once again perform their tasks of motion and support. Once the patient heals and their shoulder strength returns, they will likely find their ability to sleep on their side fully restored.


If you have persistent shoulder pain while sleeping, it could be an indication of an underlying health issue. For more information, contact Cawley Rehab at 570-208-2787 or email us at cawleyptfrank@gmail.com.