A Complete Guide to Knee Gel Injections: What to Expect

Summary and Overview

Viscosupplementation involves intra-articular injections of hyaluronic acid (HA) to manage knee osteoarthritis (OA) by supplementing the joint’s natural lubricant to reduce pain and improve function. Known as “gel shots,” these injections are a nonsurgical option alongside physical therapy, medications, and corticosteroids. While many patients experience symptom relief lasting months, results vary with factors like age, obesity, and OA severity. The safety profile is generally favorable, with mostly mild local side effects and rare systemic risks.

The efficacy of HA injections remains debated, with mixed findings from reviews and differing international guidelines—some discourage routine use due to cost-effectiveness concerns, while others support reimbursement. Knee gel injections are part of a multimodal OA management approach, including lifestyle changes, physical therapy, and emerging regenerative therapies, highlighting the need for individualized treatment plans.

Types of Knee Gel Injections

Knee injections include hyaluronic acid (HA), corticosteroids, and platelet-rich plasma (PRP). HA injections restore joint lubrication and cushioning, with most modern products lab-produced for safety. Corticosteroids provide quicker inflammation relief but are limited in frequency due to potential joint damage. PRP is experimental, using concentrated blood platelets to stimulate healing but lacks FDA approval for knee OA. Patients may receive single or multiple injections depending on treatment protocols.

Clinical Indications and Patient Selection

HA injections are indicated for knee OA patients with pain and functional limitations unrelieved by conservative treatments like NSAIDs. Radiographic evidence helps assess OA severity, but patient selection requires careful evaluation since effectiveness varies by disease stage. Contraindications include active infections and untreated joint effusion. Treatment adherence and patient preferences are important for optimizing outcomes.

Procedure

The injection involves administering HA directly into the knee joint after sterilizing the site and optionally numbing the area. Joint effusion is often aspirated beforehand. The HA gel improves synovial fluid properties, enhancing lubrication and shock absorption. Effects typically appear within weeks and can last several months; injections may be repeated biannually if beneficial. The procedure is well tolerated, with a slower onset but longer-lasting relief compared to corticosteroids.

Effectiveness and Outcomes

HA injections can improve knee function and reduce pain for several months, though responses vary. Factors like obesity, age over 65, and arthritis severity influence outcomes. Treatments usually involve one to five injections spaced weekly, with possible repeats after six months. While some question their efficacy versus placebo, many patients report delayed need for surgery and improved mobility. Other intra-articular options like corticosteroids, PRP, and stem cells are used experimentally. Knee gel injections complement a multimodal OA treatment strategy.

Safety Profile

HA injections are generally safe with mild local side effects such as pain, swelling, redness, and occasional post-injection flare. Rare systemic effects have been reported but are uncommon. Single-injection regimens reduce side effects and costs. Most adverse events stem from needle use rather than the injected substance, underscoring the importance of sterile technique and patient evaluation to avoid contraindications.

Alternatives and Complementary Treatments

OA management includes lifestyle changes, physical activity, assistive devices, and pharmacologic treatments like NSAIDs. Exercise programs and weight loss help reduce symptoms. Experimental therapies such as PRP and stem cell injections show potential but lack FDA approval and widespread validation. Physical therapy and hydrotherapy often accompany injections to enhance results. Knee gel injections offer a less invasive alternative to surgery and may delay surgical intervention in some patients.

Patient Experience and Expectations

Patients with mild to moderate knee OA typically notice pain relief and improved function within 4 to 6 weeks of HA injections, lasting up to six months. Treatment may involve a single injection or a series of three weekly injections depending on the case. The procedure is quick, office-based, and low risk, with temporary soreness as a common side effect. Effectiveness varies, with factors like obesity and arthritis severity influencing outcomes. Careful patient assessment helps identify those most likely to benefit.

Research and Guidelines

Numerous randomized controlled trials have assessed HA injection efficacy and safety for knee OA, with varying study designs. Ongoing research aims to clarify patient selection and optimize treatment protocols amidst mixed clinical guideline recommendations worldwide.

The content is provided by Sierra Knightley, Scopewires