Thoracic outlet syndrome worse at night: what to know

The thoracic outlet is a passageway for nerves and blood vessels traveling from the neck into the arm. Raising an arm, sleeping with the shoulder rolled forward, or resting the head on the arm can increase pressure in this area. You may notice arm numbness and tingling, hand numbness, aching, heaviness, or a change in hand temperature or colour. Symptoms can affect one side or both sides and do not by themselves confirm the cause. Read more about [Thoracic Outlet Syndrome](/conditions/thoracic-outlet-syndrome/), [Arm Numbness and Tingling](/symptoms/arm-numbness-and-tingling/), and [Hand Numbness](/symptoms/hand-numbness/).

Try keeping the neck neutral and the shoulder supported rather than sleeping with the arm overhead. A pillow supporting the upper arm may reduce traction, while changing position when symptoms begin can prevent prolonged pressure. During the day, avoid carrying heavy bags on the affected side and take breaks from sustained reaching. A clinician or physiotherapist can assess posture, shoulder movement, nerve function, and circulation, then tailor exercises. [Physiotherapy](/treatments/physiotherapy-and-rehabilitation/physiotherapy/) and [Postural Correction Therapy](/treatments/physiotherapy-and-rehabilitation/postural-correction-therapy/) may be considered when appropriate.

Arrange medical assessment if symptoms persist, interfere with sleep, or are becoming more frequent. Seek urgent care for a suddenly cold, pale, blue, or markedly swollen arm; severe weakness; new loss of movement; chest pain; or trouble breathing. These features can indicate a circulation or nerve problem needing prompt evaluation.

Could my sleeping position be compressing a nerve or blood vessel? Which examination findings would distinguish thoracic outlet syndrome from a neck or wrist problem? What exercises and positions should I avoid initially? Do I need assessment of circulation or nerve function?