OrthoGlide™ May Offer a Smooth Ride for Knees
OrthoGlide is a new implant that replaces worn cartilage inside the knee, offering patients younger than 55 years a less invasive alternative to total knee replacement.
The knee joint has three compartments: medial (inside), lateral (outside), and patellofemoral (front, or knee cap). Knee osteoarthritis due to cartilage breakdown often starts in the medial compartment. Patients slowly become bow-legged, which increases pressure and causes pain on the inside of the knee.
How It Works
OrthoGlide is a metallic, wedge-shaped device that is inserted into the knee’s medial compartment to relieve pressure, restore proper joint alignment, redistribute the load more evenly to the outside of the knee, and increase stability by tightening loose ligaments. The mobile (uncemented) device rests on top of the tibia, and is held in place by gravity and a small lip at the back designed to prevent it from slipping forward and out of position.
Patients receive general anesthesia or a spinal block and the OrthoGlide device is inserted through a 5-cm to 7-cm incision during a 45- to 60-minute operation. Patients can often go home the same day, with minimal post-operative restrictions.
The device may allow total knee replacement to be delayed until patients are older and less likely to require a second knee replacement.
Who Might Benefit
About 3,000 Canadians under the age of 54 underwent total knee replacement in 2004-2005. OrthoGlide is indicated for patients under 55 years of age with moderate knee osteoarthritis involving only the medial compartment, pain primarily on the inside of the knee, minimal or no degeneration in the lateral or patellofemoral compartments, intact ligaments, and bow-leggedness on x-ray. Fewer than 1% of patients with knee osteoarthritis are appropriate candidates for OrthoGlide and all conservative treatment options should be tried first, including medication, injections, and exercise. OrthoGlide may be an alternative for obese patients, who are often poor candidates for other knee surgeries.
OrthoGlide™ (Advanced Bio-Surfaces, Inc.) was licensed by Health Canada and by the US Food and Drug Administration in 2006.
There are no published trials of OrthoGlide. The evidence to support its use is based on studies of similar devices, such as the UniSpacer® (Zimmer, Inc.). Two brief reviews of the literature on the UniSpacer device concluded there was insufficient evidence to establish long-term safety and efficacy.[6,7]
The Canadian cost for the OrthoGlide device is unavailable, but the US price is US$4,500. According to the manufacturer, 220 patients have received OrthoGlide implants, although the implant has not been used in any Canadian patients to date.
 Emerson RH, et al. J Bone Joint Surg Am 1985;67(2):208-12.
 Hallock RH. Orthop Clin North Am 2005;36(4):505-12.
 Orthoglide technical description. Advanced Bio-Surfaces; 2007. Available: http://www.advbiosurf.com/orthoglide_products.html
 CJRR report: total hip and total knee replacements in Canada. Ottawa: Canadian Institute for Health Information; 2006. Available: http://secure.cihi.ca/cihiweb/dispPage.jsp?cw_page=PG_387_E&cw_topic=387&cw_rel=AR_ 30_E
 Scott RD, et al. Current Opinion in Orthopedics 2005;16(1):35-7.
 ECRI Institute. Unicondylar interpositional spacer systems for osteoarthritis of the knee. In: HTAIS Hotline Service [database online]. Plymouth Meeting (PA): ECRI Institute; 2007.
 Tice JA. Knee joint spacer (Unispacer) system for osteoarthritis of the knee. San Francisco: California Technology Assessment Forum (CTAF); 2003. Available: http://www.ctaf.org/content/general/detail/552