Thoracic Outlet Syndrome (TOS) occurs when nerves or blood vessels become compressed in the space between the collarbone and the first rib.
TOS can cause pain, tingling, numbness or weakness in the shoulder, arm and hand (Jones et al., 2019). Unfortunately, these symptoms can become more noticeable at night. This is especially true if your sleeping position places extra pressure on the shoulder or upper chest.
In this article, we’ll explore the best Thoracic Outlet Syndrome sleeping position suggestions, while analysing how your pillow setup and sleeping habits can lead to a better night’s sleep.
Why Your Shoulder Position Matters More Than Your Mattress
While it's easy to blame your mattress for overnight discomfort, your shoulder position often plays a much bigger role when it comes to Thoracic Outlet Syndrome discomfort.
In fact, most medical professionals suggest physical therapy and posture correction before any other treatments (Kaplan and Kanwal, 2023). That’s why knowing how to sleep with Thoracic Outlet Syndrome can make a significant difference.
The thoracic outlet is a narrow space, so sleeping in positions that place additional pressure on this area may increase compression and aggravate symptoms.
Common factors that can contribute include:
- Shoulders rolling forwards while sleeping
- Sleeping with one or both arms overhead
- Compression around the collarbone
- Poor neck support increasing tension through the upper body
Experts generally suggest keeping your shoulders relaxed and your upper body well supported, as these factors can help minimise unnecessary pressure while you sleep.
Finding the Right Pillow Height for Your Neck
Your pillow plays an important role in keeping your head and neck comfortably aligned throughout the night.
If your pillow is too high, your neck may bend sideways or forwards. If it's too flat, your head may not receive enough support. Both can increase tension through the neck, shoulders and upper back.
An adjustable pillow makes it easier to find the height that feels right for you. The Groove Adjustable Pillow allows you to add or remove filling to customise the loft, helping you maintain a more neutral neck position whether you sleep on your back or side, while simultaneously providing comfortable rest.
Supporting the Arm to Reduce Compression
Another of the simplest ways to improve comfort during sleep is to support the affected arm rather than letting it rest unsupported or in an awkward position. Poor posture can increase compression, which can worsen symptoms (Mayoclinic.org, 2026).
For side sleepers, hugging a body pillow (also known as a full-length pillow) helps support the shoulder, chest and arm together. This can help prevent the shoulder from collapsing forwards while keeping the arm gently elevated, a position commonly recommended by physiotherapists to help reduce compression around the thoracic outlet.
The Groove Body Pillow is a good Thoracic Outlet Syndrome pillow option that can provide full-body support, helping you maintain a more comfortable sleeping position throughout the night.
Keeping Your Spine Aligned While Side Sleeping
Good alignment starts with your neck but shouldn't stop once you reach the shoulders. Keeping the shoulder girdle and upper thorax—the top of your chest and base of the neck—in alignment can provide relief (Watson, Pizzari and Balster, 2010).
When sleeping on your side, placing a pillow between your knees helps keep your pelvis level and reduces twisting through your spine. This allows your shoulders, hips and lower back to remain in a more natural position, helping your whole body feel better supported, and it’s therefore considered one of the best sleeping positions for Thoracic Outlet Syndrome
The Groove Combination Pillow is designed to support comfortable side sleeping with ergonomic leg support. This allows the upper body to remain relaxed while encouraging better alignment from head to toe, thanks to comfortable straps and a memory-foam design.
Sleeping Habits That Can Make TOS Worse
Certain sleeping habits may increase pressure around the thoracic outlet and make symptoms feel worse by morning. If you have TOS, it’s critical to take note of these common mistakes.
These include:
- Sleeping directly on the affected shoulder
- Sleeping with one or both arms above your head
- Using a pillow that's too high or too flat
- Allowing the shoulders to round forwards or upwards during sleep
- Sleeping on your stomach, which often keeps the neck and shoulders rotated for long periods
It’s recommended to make gradual changes to your sleep setup. Slowly eliminate the poor habits and add sleep aids to support your body.
Best Sleeping Position For Thoracic Outlet Syndrome
Looking for the best sleeping position for Thoracic Outlet Syndrome? The reality is that here isn't one perfect sleeping position that works for everyone.
However, but posture adjustments may help improve comfort overnight:
- Adjust your pillow height until your neck feels neutral
- Support the affected arm rather than letting it hang unsupported
- Use a body pillow to help keep your shoulder comfortably positioned
- Place a pillow between your knees when side sleeping to encourage whole-body alignment
Rather than embodying one position, with TOS the goal is to create a relaxed sleeping posture that supports your body without placing unnecessary pressure on your shoulders or upper chest.
Call to Action
If Thoracic Outlet Syndrome is disrupting your sleep, a better night’s rest is not far away. Improving your pillow setup may help reduce pressure on the shoulder and upper chest while supporting better spinal alignment.
Support your TOS with a Groove Pillow. The Groove Adjustable Pillow, Groove Body Pillow, and Groove Combination Pillow all provide specialised support and can improve your comfort today.
References
- Jones, M.R., Prabhakar, A., Viswanath, O., Urits, I., Green, J.B., Kendrick, J.B., Brunk, A.J., Eng, M.R., Orhurhu, V., Cornett, E.M. and Kaye, A.D. (2019). Thoracic Outlet Syndrome: A Comprehensive Review of Pathophysiology, Diagnosis, and Treatment. Pain and Therapy, 8(1), pp.5–18. doi:10.1007/s40122-019-0124-2.
- Kaplan, J. and Kanwal, A. (2023). Thoracic Outlet Syndrome. [online] PubMed. Available at: https://www.ncbi.nlm.nih.gov/books/NBK557450/ [Accessed 9 July 2026].
- Mayoclinic.org. (2026). A collaborative and conservative approach to neurogenic thoracic outlet syndrome - Mayo Clinic. [online] Available at: https://www.mayoclinic.org/medical-professionals/surgery/news/a-collaborative-and-conservative-approach-to-neurogenic-thoracic-outlet-syndrome/mac-20599405 [Accessed 9 July 2026].
- Watson, L.A., Pizzari, T. and Balster, S. (2010). Thoracic outlet syndrome Part 2: Conservative management of thoracic outlet. Manual Therapy, [online] 15(4), pp.305–314. doi:10.1016/j.math.2010.03.002.