To cater to an ever-expanding aging population, treatments to manage conditions that are prevalent in the elderly are increasing in number. Patients receiving these treatments should be knowledgeable about the different modalities and medications in order to determine the right treatment for their lifestyle and condition. Here, we compare Synvisc, a popular injection used in the treatment of knee osteoarthritis, with its single-dosing-regimen, Synvisc One, in terms of their respective benefits and drawbacks.

Osteoarthritis of the knee

Patients who complain about joint stiffness, pain, and swelling may be suffering from a form of arthritis that affects the bone called osteoarthritis. With this condition, the damage inflicted by the wear and tear that affects weight-bearing joints, such as the knees, is accelerated due to the degradation of protective cartilage at the ends of the bones. These effects lead to the development of inflammation in joints and the subsequent disease state.
This condition, if severe, can be debilitating, as the pain and swelling makes it hard for the patient to perform activities like walking, playing sports, or exercising. Mobility may also be restricted, which can have a negative impact on the patient’s quality of life. This condition predominantly affects the aging, the obese, and those with a prior injury to the knee.
This condition is progressive and has no known cure. However, certain types of medical therapies are available that can help the patient to relive symptoms of osteoarthritis and slow down or prevent the further progression of this degenerative condition. Such therapies include taking analgesics, such as acetaminophen; anti-inflammatory medications, including injections of cortisone to the knee; undergoing physical therapy to strengthen the muscles surrounding the knee; and/or undergoing weight loss management that can help to decrease stress on the knee.

The role of viscosupplements in the treatment of osteoarthritis

Hyaluronic acid injections are a common type of treatment given to patients who have not responded adequately to the standard therapies used to treat osteoarthritis, which include the therapies mention above. They are classed as viscosupplements because they are administered as a means of restoring the normal rheological environment in the joint so as to re-establish the lubrication and cushioning effects that are often lost with the development of osteoarthritis. The benefits of viscosupplements have been well-documented, and its effects having been shown to last for several months. There are multiple types of viscosupplementation products, each with its own composition, duration of effect, and recommended dosing regimens.
Synvisc and Synvisc One are two such viscosupplements. They are unique from other viscosupplements in that they are primarily composed of hylan, a high-molecular-weight, cross-linked derivative of hyaluronic acid. The primary compound is one that is cross-linked and made up of two types of hylan: hylan A and hylan B. Hylan A is a 6000kDa soluble molecule that makes up 80% of the compound in terms of volume. Hylan B is an insoluble gel-like molecular network that makes up 20% of the compound in terms of volume. In Synvisc and Synvisc One, these hylan compounds are contained in a buffered physiological sodium chloride solution. Synvisc and Synvisc One have greater viscoelastic properties than natural hyaluronic acid, and their properties are comparable to that of healthy human synovial fluid.

Who should not use Synvisc and Synvisc One?

Synvisc and Synvisc One are indicated for the treatment of knee osteoarthritis in patients that have failed to adequately respond to the condition’s conventional therapies, such as pain medications and physical therapy. Patients who are not good candidates to receive Synvisc or Synvisc One treatments are those with a known hypersensitivity (allergy) to hyaluronan (sodium hyaluronate) preparations and/or avian proteins, feathers, and egg products, since Synvisc and Synvisc One are derived from chicken/rooster combs, which are obviously avian sources. As with any intraarticular injection, following sterile precautions is crucial to preventing the occurrence of septic arthritis. Hence, Synvisc and Synvisc-One should not be injected in the knees of patients that have skin diseases, knee joint infections, and/or infections in the area of the injection site.

How do Synvisc and Synvisc One differ from each other?

Synvisc is exactly the same as Synvisc One. They only differ in terms of their respective dose regimen. While Synvisc is administered in a series of three weekly sessions consisting of 2ml injections, Synvisc One is a combination of the three Synvisc doses given in a single 6ml injection. Both have similar efficacy profiles, and both are comparable in terms of safety and tolerability. Both treatments can be safely repeated.
There are several benefits to having a single-dose regimen as opposed to a multi-dose regimen. To start, with every added injection, the risk for contracting an infection or other local adverse reactions increases. A single-dose regimen negates that risk, as it decreases the need to repeatedly disturb the sterile intra-articular environment. Hence, a single-dose regimen can potentially decrease the risk of septic arthritis and other local comorbidities occurring.
In addition, a single-dose regimen also means fewer visits to the doctor. This will, in turn, allow for better patient compliance, improved convenience, and lower medical expenses, as the patient will not have to pay for additional visits.


Synvisc and Synvisc One are treatments used in managing knee osteoarthritis, and they are effective in improving the condition’s symptoms, such as joint pain and swelling. Synvisc and Synvisc One differ only in terms of their respective dosing regimen. The benefits to be gained by following a single-dose regimen, which include increased convenience and a lower medical cost, may compel patients to pursue Synvisc One.