Ossur Unloader One X Knee Brace – Clinically Proven Relief for Knee Osteoarthritis, Bone-on-Bone Pain & Meniscus Tears
The Ossur Unloader One X is the gold-standard unloader knee brace for patients with unicompartmental knee osteoarthritis (OA), bone-on-bone knee pain, degenerative meniscus tears, and related conditions. Using Össur's patented 3-Point Leverage System and SmartDosing™ dials, it biomechanically shifts load away from the damaged compartment — delivering measurable, adjustable pain relief without surgery.
🦵 How to Choose the Right Unloader One X for Your Knee
This brace comes in several versions. Answer these 4 quick questions to find your exact match — or share your prescription with us and we’ll confirm your selection.
Step 1 — Which knee is painful?
→ Choose Right
→ Choose Left
Step 2 — Where is your knee pain located?
Stand with your feet together. Look at your painful knee.
(toward your other leg — the most common type)
Your knee may bow inward (varus / bow-legged)
→ Choose Medial
(away from your other leg)
Your knee may bow outward (valgus / knock-kneed)
→ Choose Lateral
💡 Not sure? Check your X-ray report or ask your doctor — it will say “medial compartment OA” or “lateral compartment OA.”
Step 3 — Standard or Short frame?
Full-length frame. Best for most patients. Recommended for active use and maximum stability.
Shorter frame. Better for shorter legs, patients with sensitive skin behind the knee, or those who find the standard frame uncomfortable.
💡 If your doctor prescribed a specific frame length, follow their recommendation. When in doubt, Standard is the most commonly prescribed.
Step 4 — What is your thigh circumference?
Measure around your thigh 6 inches (15 cm) above the center of your kneecap while standing. If you are on the border between sizes, we suggest you move to the next size up, especially if you have frequent swelling.
| Size | Thigh Circumference | Part Number Examples |
|---|---|---|
| XS – M |
13–19" (33–48 cm) |
UOX0518713, UOX0618713, UOX1518713 |
| L – XL |
19–26" (48–66 cm) |
UOX0518715, UOX0618715, UOX1518715 |
📋 Quick Reference: Variant Name Decoder
Each variant name follows this pattern: [Frame] [Side] [Compartment] [Size]
Example: "Standard Right Medial XS-M" = Full-length frame · Right knee · Inside pain · Smaller thigh
Example: "Short Left Lateral L-XL" = Short frame · Left knee · Outside pain · Larger thigh
❓ Still unsure? Your prescription or fitting notes from your doctor or physical therapist will specify the exact variant. You can also contact us and we’ll help you confirm the right choice.
How to Measure & Apply — Watch These Videos:
Ideal Conditions for the Unloader One X
- Unicompartmental knee osteoarthritis (medial or lateral)
- Bone-on-bone knee pain
- Degenerative meniscus tears
- Cartilage repair recovery
- Bone bruises (bone marrow lesions)
- Avascular necrosis of the knee
- Tibial plateau fractures and post-surgical support
Key Features
- ✅ Clinically Proven Pain Relief: Össur’s 3-Point Leverage System and Dynamic Force Straps reduce pressure on the arthritic or injured compartment.
- ✅ SmartDosing™ Dials: Tool-free tension control lets you fine-tune offloading throughout the day.
- ✅ No-Slip Fit: Anti-migration calf strap keeps the brace securely in place during activity.
- ✅ All-Day Comfort: Soft, breathable liners minimize pressure points and skin irritation.
- ✅ Easy Application: Color-coded guides and alignment markings for fast, correct donning.
- ✅ Discreet Low-Profile Design: Slim frame fits under most clothing.
- ✅ Machine Washable: Durable, easy-care materials — wash bag included.
- ✅ Available in Standard & Short frames to accommodate a wide range of leg lengths and body types.
FSA/HSA Eligible — HCPCS Code: L1843
Shipping: Ships from NJ or CA warehouse in 2–3 business days.
OrthoTape.com is an authorized Össur dealer. Authentic product. Full manufacturer warranty. Use as directed by your surgeon or clinician.
This product is intended to support and offload the knee joint. It is not a substitute for professional medical advice, diagnosis, or treatment. Always follow the guidance of your physician or licensed healthcare provider regarding use of orthopedic bracing.
Frequently Asked Questions
What is knee osteoarthritis and why does it cause bone-on-bone pain?
Knee osteoarthritis (OA) is a degenerative joint disease in which the articular cartilage — the smooth cushioning tissue that covers the ends of the bones — gradually breaks down. As cartilage wears away, the space between the femur (thigh bone) and tibia (shin bone) narrows. In advanced OA, this cartilage is completely gone, causing the bones to rub directly against each other — a condition commonly called “bone-on-bone.” This produces pain, swelling, stiffness, and reduced range of motion, particularly with weight-bearing activities like walking, climbing stairs, or standing for extended periods.
How does an unloader knee brace actually relieve OA pain?
An unloader brace works by applying a controlled three-point bending force to the knee, which shifts the mechanical load away from the damaged compartment and onto the healthier side of the joint. The Ossur Unloader One X uses a patented 3-Point Leverage System with SmartDosing™ dials to precisely control the amount of offloading. Clinical studies have shown that properly fitted unloader braces can significantly reduce pain, improve function, and delay the need for knee replacement surgery in patients with unicompartmental OA.
Can an unloader brace help me avoid or delay knee replacement surgery?
Yes — for many patients with unicompartmental OA, an unloader brace is a proven conservative treatment that can significantly delay or even eliminate the need for knee replacement surgery. Multiple peer-reviewed studies have demonstrated that consistent use of an OA unloader brace reduces pain, improves activity levels, and slows disease progression. Orthopedic surgeons frequently prescribe unloader braces as a first-line non-surgical intervention, particularly for younger or more active patients who want to remain active while managing their OA.
What is the difference between medial and lateral knee OA, and how do I know which I have?
The knee joint has two compartments: the medial (inner) compartment on the side closest to your other leg, and the lateral (outer) compartment on the outside. Medial compartment OA is by far the most common, often associated with a varus (bow-legged) alignment. Lateral compartment OA is less common and typically associated with valgus (knock-kneed) alignment. Your doctor’s X-ray report or prescription will specify which compartment is affected — look for the terms “medial compartment OA” or “lateral compartment OA.” Choosing the correct medial or lateral version of the brace is critical for effective offloading.
Can I wear the Unloader One X during sports and physical activity?
Yes. The Ossur Unloader One X is specifically designed for active patients and is one of the most activity-friendly OA braces available. Its low-profile frame, anti-migration calf strap, and SmartDosing™ tension control make it suitable for walking, hiking, cycling, golf, and other low-to-moderate impact activities. Many patients report being able to return to activities they had abandoned due to knee pain. Always consult your physician or physical therapist regarding appropriate activity levels for your specific condition and stage of OA.
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