Osteoarthritis of the knee is a widespread condition where the protective cartilage cushioning the ends of the bones wears down over time. This deterioration causes pain, stiffness, and reduced mobility, significantly impacting daily life. When initial treatments like pain relievers and physical therapy fail to provide adequate relief, non-surgical options are often explored to manage the symptoms. One increasingly popular approach is the use of injectable treatments commonly known as “gel shots.” This method offers a way to supplement the joint’s natural fluid, providing temporary relief. Understanding how often this treatment can be safely and effectively repeated is crucial for anyone considering this therapeutic path.
Defining Viscosupplementation (The “Gel Shot”)
The formal medical term for this injection is viscosupplementation, which involves administering a gel-like fluid directly into the knee joint space. This fluid is made of hyaluronic acid (HA), a substance that occurs naturally in the body, particularly in the synovial fluid surrounding the joints. Healthy synovial fluid is thick, elastic, and acts as both a lubricant to reduce friction and a shock absorber.
In a knee affected by osteoarthritis, the natural hyaluronic acid breaks down, reducing its concentration and protective properties. The viscosupplementation injection supplements this diminished fluid, aiming to restore the joint’s ability to move smoothly and absorb forces. The treatment helps to decrease pain and improve joint function. This therapy is typically recommended for patients with mild to moderate osteoarthritis who have not found sufficient relief from more conservative treatments.
Standard Treatment Regimens and Expected Duration
Viscosupplementation is administered in specific protocols that depend on the product used, as several different formulations of hyaluronic acid are commercially available. Treatment can involve either a single, highly concentrated injection or a series of injections spread out over several weeks. The multi-injection regimen typically consists of three to five separate shots given weekly.
The full effect of the treatment is often not immediate; patients sometimes need to wait several weeks after the final shot to experience significant pain relief. Clinical studies generally indicate that the pain-relieving effects of a complete course of injections last for an average duration of four to six months. This expected period of efficacy is a primary factor in determining when retreatment may be necessary.
The need for retreatment is determined by the return of symptoms, meaning the pain and stiffness begin to interfere with daily activities once more. While some individuals may experience relief for up to a year, the four-to-six-month window is the standard benchmark for when the benefits are expected to diminish. The decision to repeat the procedure is based on the patient’s symptomatic response after the expected duration of the previous course has passed.
Mandatory Waiting Periods and Maximum Annual Frequency
While the return of symptoms indicates the need for retreatment, medical guidelines impose a minimum waiting period between courses of viscosupplementation for safety and regulatory reasons. Regardless of how quickly the pain returns, physicians must adhere to a minimum interval, which is typically six months, before starting a new course of injections. This mandatory waiting period is designed to limit the overall exposure to the injected substance. The U.S. Food and Drug Administration (FDA) approved these devices with specific treatment schedules that often include this six-month safety buffer. This interval means most patients receive a maximum of two full courses of viscosupplementation annually. A physician will only approve retreatment after evaluating the severity of returning symptoms and confirming the patient responded well to the previous injections.