By the BioRestLab Editorial Team · Last reviewed: October 2026
Quick verdict
Our pick: Sports Medica Memory Foam Knee Pillow. BioRestLab Rating: 6.6/10.
Best for: side sleepers who want a simple, firm pillow that keeps the knees and hips stacked.
Skip it if: you want one pillow you can also use under the knees on your back; see the alternatives below.
Affiliate links: BioRestLab may earn a commission from qualifying purchases made through some links on this page, including as an Amazon Associate, at no extra cost to you.
If you read our guide to the best sleeping position for lower back pain, you will know that a pillow between the knees is a low-cost change worth testing if side sleeping feels unsupported. Here is a close look at one of the most consistently well-reviewed knee pillows on Amazon, and how it compares with two widely bought alternatives.
Why a Knee Pillow Can Help: What the Evidence Says
Without support, the top leg of a side sleeper tends to slide forward, rotating the pelvis and twisting the lower back. A firm pillow between the knees keeps the hips stacked and the spine closer to a neutral position. That mechanical rationale is plausible and widely used in practice, but it should be described as a comfort and positioning aid, not a treatment.
The research is limited and indirect. A 2025 systematic review found that supported side-lying was associated with better outcomes in the available studies on sleep posture and low back pain, while noting that the literature is small. We did not find clinical trials of knee pillows as a product category, and none of this specific product.
Our Pick: Sports Medica Memory Foam Knee Pillow
This is a straightforward, fixed-shape contour pillow: firm memory foam shaped to sit between the knees, with a removable, washable cover and an optional strap. We chose it for its large base of verified-purchase ratings and a simple design that matches the use case. We have not tested it hands-on. The listing describes the pillow as doctor-developed; we have not verified that claim, and it does not change our rating.
What Verified Buyers Report (Owner Feedback, Not Clinical Evidence)
- Comfort when side sleeping: many reviewers say it makes side sleeping more comfortable around the hips and lower back. Some mention sciatica; these are individual experiences, not evidence that the pillow treats any condition.
- Durability concern: a recurring theme is that the foam softens or flattens after long-term nightly use, so expect to replace it eventually.
- Strap is optional: several buyers say they never use the retention strap and the pillow still stays in place.
How It Compares
| Pillow | Shape | Best for | Cover | Trade-off |
|---|---|---|---|---|
| Sports Medica (our pick) | Fixed contour, knee-only, optional strap | Simple, dedicated knee support | Removable, washable | Foam softens over long-term use |
| Everlasting Comfort | Dual-concave contour, removable strap | Side sleepers whose pillow slips out during the night | Removable, machine-washable | Bulkier between the legs; some find it too firm at first |
| 5 STARS UNITED | Contour, no strap; multi-position | Switching between side and back (can sit under the knees) | Breathable cover; check listing for washing | No strap, so it can move if you turn often |
Details in this table come from the current Amazon product listings (manufacturer information), not from our own hands-on testing. Check the listing before buying.
Who Should Buy This
A good fit if you sleep on your side, your top knee tends to drop forward, and you want the simplest option: a pillow that sits between your knees with no adjustment. If you switch between side and back sleeping, a multi-position contour such as the 5 STARS UNITED is more versatile; if your pillow keeps slipping out at night, a strapped design such as the Everlasting Comfort may suit you better. If hip, leg or back pain is the main reason you are shopping, read the medical note below first.
Sports Medica Memory Foam Knee Pillow
Check the current price and availability, then compare it with the alternatives discussed in this guide.
Affiliate links: BioRestLab may earn a commission from qualifying purchases made through some links on this page, including as an Amazon Associate, at no extra cost to you.
Related BioRestLab Guides
Sources and Further Reading
- Relationship between sleep posture and low back pain — systematic review (2025)
- Sleep posture and non-specific spinal symptoms — scoping review
This article is for general educational purposes and is not a substitute for professional medical advice. If hip, leg or back pain is severe, persistent, or accompanied by numbness or weakness, see a doctor.