Shoulder discomfort during sleep is often linked to pressure that builds when the body remains in one position for several hours. This issue is particularly common among side sleepers, as the shoulder becomes one of the primary contact points with the mattress.
If the sleep surface does not allow the shoulder to settle naturally, pressure may accumulate in the joint and surrounding tissues.
Why shoulders become pressure points
The shoulder joint has a relatively shallow socket that allows a wide range of movement. While this mobility is beneficial for daily activity, it also makes the joint more sensitive to prolonged pressure.
When lying on the side, the shoulder carries a significant portion of body weight. If the mattress is too firm or does not contour effectively, the shoulder may remain elevated relative to the rest of the body.
The impact on surrounding muscles
Pressure in the shoulder can compress muscles and ligaments that stabilise the joint. Over time this compression may cause discomfort or numbness in the arm.
The body may respond by shifting position to relieve pressure, which can interrupt sleep cycles.
The relationship between shoulder pressure and the spine
When the shoulder cannot settle into the mattress, the upper spine may tilt sideways. This misalignment can place strain on muscles in the neck and upper back.
Maintaining balanced pressure across the shoulder region helps keep the spine aligned and reduces tension in surrounding muscles.
References
American Chiropractic Association
Sleep Research Society