Synvisc Products

What is Synvisc?

It is an animal-based orthopaedic implant designed to alleviate pain and discomfort in synovial joints affected by arthritis. Its active ingredient is 8mg/mL of chemically cross-linked hylan derived from rooster combs—the fleshy crest on top of rooster heads. Other ingredients include 8.5mg/mL of sodium chloride, 0.16mg/mL of disodium hydrogen phosphate, 0.04mg/mL of sodium dihydrogen phosphate hydrate, and water for injection. The resulting gel is very viscoelastic, bioresorbable, and tissue-friendly. There are 2 different products available in the Synvisc product range, and each have a different volume of product supplied in a single syringe. Nevertheless, the implant formulation is exactly the same:

1. Synvisc: The orthopaedic implant comes in a prefilled 2mL syringe and each box contains 3 preloaded syringes, labels to ensure traceability, and a device manual. Patients should receive 3 injections for the best outcome.
2. Synvisc One: This single-dose orthopaedic implant comes in a prefilled 6mL syringe and each box contains only 1 syringe, labels to ensure traceability, and a device manual. Just a single dose is adequate to deliver ideal pain-relieving actions.

For both of the above products, needles are to be obtained separately according to the joints being treated. The fragile packaging is sterile and must be kept in a clean room with temperature ranging between 2ºC to 30ºC, shielded from light. This product is manufactured by Genzyme.

What is it used for?

Synvisc is used to correct the effects of painful arthritis and other debilitating symptoms in various synovial joints, especially for patients who have not found successful treatment with non-pharmacological therapies (e.g. mobility support gears, analgesics, oral supplements, etc.). Some of the specific areas that are frequently treated with this injectable solution include:

• Hip: The hip joint is a type of ball and socket synovial joint formed between the hip bone and the thigh bone. Being one of the largest weight-bearing joints, it provides stability to body.
• Knee: The knee is a modified synovial hinge joint formed between 3 bones: the femur (thigh bone), the tibia (shin bone), and the patella (kneecap). Besides helping us to move, the knee also supports the body’s weight.    
• Shoulder: The shoulder is made of 3 bones: the scapula (shoulder blade), the clavicle (collarbone), and the humerus (upper arm bone).
• Ankle: The ankle is made of 3 bones: talus (in the foot), the tibia, and the fibula (in the leg). This synovial hinge joint is responsible for movement between the leg and foot.

How does it work?

The synovial joint is marked by its flexibility and synovial fluid. The ends of the bones encompassed within the synovial membrane are protected with a layer of articular cartilage. This cartilage continuously secretes synovial fluid into the joint space, in a process called weeping lubrication. At its prime, synovial joints provide smooth movement while absorbing sudden shocks. However, degenerative disorders emerge when this string cartilage breaks down, resulting in a sharp decline of lubricating fluid. This causes the bones to grind excruciatingly against each other, inducing inflammatory responses in neighbouring tissues. If left untreated, patients may lose complete mobility due to agonising pain and stiffness. Synvisc acts as a viscosupplement and shares almost identical viscoelastic properties to naturally-occurring synovial fluid. Once injected, it replenishes the lost fluid and lubricates the bones so they glide over each other smoothly. Consequently, pain and discomfort is alleviated, and patients can resume their daily activities with greater ease.

How to inject Synvisc?

Injecting Synvisc is considered a medical procedure and can only be conducted by licensed physicians with vast experience in injecting orthopaedic implants. It is also important to adhere to stringent aseptic techniques to ensure a minimal risk of infection and cross-contamination. Before administering the implant, it is very important to thoroughly sanitise the treatment area and remove any fluid build-up from the affected joints. Needles sizes of 18G to 22G are recommended depending on the joints being treated. Inject the implant intra-articularly into the synovial space of the problematic joint. After the session is completed, discard any remaining gel and used needles in accordance with proper procedure. As part of aftercare, advise your patients to apply a cold compress to the treated area and to avoid high impact activities like tennis and jogging. You can also prescribe oral analgesics to provide greater comfort to your clients while any side effects from the injection clear up. 

How often to use?

The injection sessions are scheduled differently depending on which variation of the product is used:

1. Synvisc: Administer 1 injection weekly for a total of 3 injections on the affected knee joints. The maximum dosage is 6 injections within 6 months, with a minimum 1 month break between sessions. Other joints like the hips, shoulders, and ankles may only need 1 injection for improvement. However, a second injection can still be given 1 to 3 months after the initial treatment session if patients do not regain comfort and mobility.
2. Synvisc One: This is a single-dose implant, which means the entire 6mL syringe is adequate to treat a joint in a single session.

How long does it last?

Patients can notice improvements within a month after completing treatment, and these desirable effects can last for approximately six months. Since the implant is completely biodegradable, it will disintegrate into the nearby tissues, at which point patients can obtain more viscosupplement injections as necessary. The duration of the effect of the implant varies greatly depending on patients’ age, health status, and lifestyle choices.

Is this product safe?

Yes, Synvisc implants are very safe and effective, as the active ingredients are sourced from high-quality materials. Its active ingredient—hylan—is derived ethically from rooster combs, and 2 decades of research has been proven it to be tolerated well by the human body. The resulting gel is also purified to ensure a very low risk of inducing immunogenic reactions. That being said, some people are still contraindicated from this viscosupplement, including:

• Patients who are allergic to avian products (e.g. eggs, feathers, poultry);
• Patients who are younger than 18 years old;
• Patients who are pregnant or breastfeeding.

Do not inject this implant on joints with active skin inflammation or infections. 

Synvisc side effects

Patients might experience some common after effects caused by the injection process.

Common side effects:

• Pain on treated joint
• Irritation on treated joint
• Fluid build up on treated joint
• Swelling on treated joint
• Sensation of heat on treated joint

These reactions are usually very moderate in nature and will subside within a couple of days. Patients can reduce downtime by following the recommended aftercare methods, such as applying ice packs and avoiding very strenuous exercise sessions for at least 48 hours following treatment. On rare occasions, some serious reactions have been reported by some patients. 

Serious side effects:

• Difficulty swallowing/breathing/talking
• Hives
• Nausea/vomiting
• Headache/dizziness
• Muscle ache
• Fever/chills
• Increased heart rate

These symptoms indicate an allergic attack, which can be fatal if left untreated. Patients must get immediate treatment at the nearest hospital if these symptoms appear.

What is it made of?

Synvisc is an animal-based viscosupplement designed to alleviate pain in joints damaged by degenerative diseases like osteoarthritis. This orthopaedic implant gel is viscoelastic, bioresorbable, and tissue-friendly. The active ingredients are 8mg/mL of chemically cross-linked hylan, accompanied by other gel constituents like 8.5mg/mL of sodium chloride, 0.16mg/mL of disodium hydrogen phosphate, 0.04mg/mL of sodium dihydrogen phosphate hydrate, and water for injection. Hylan is ethically harvested from rooster combs. After completing treatment, the lubricating synovial fluid is replenished, resulting in minimal pain and discomfort in the affected areas during movement.