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FAQs on Joint Injections (Hyaluronic Acid, Steroid, PRP, Stem Cells) in Phoenix, Arizona


Arthritis of the joints is a major problem. There are many treatments for painful joints. Among those measures that work the best are joint injections, including hyaluronic acid, corticosteroid, platelet-rich plasma (PRP), and stem cells.

What causes pain of the joints?

With osteoarthritis, and other joint diseases the pain often worsens as the condition progresses. Genetic predisposition also contributes to chronic knee pain. With inflammation and cartilage wear, inflammatory agents are released. These agents can sensitize main afferent nerves, which cause painful joints. The co-existence of many pathologies also contribute to joint pain.

What are corticosteroid injections?

Corticosteroids are medications that will reduce inflammation in the joint. These drugs include betamethasone sodium phosphate, betamethasone acetate, methylprednisolone acetate, dexamethasone, and triamcinolone. Some studies show that functional outcomes are much improved with corticosteroid joint injections. In a large Cochrane Review, short-term efficacy of steroid joint knee injections was confirmed.

What are hyaluronic acid (HA) injections?

Called viscosupplementation, hyaluronic acid injections are used to alleviate joint pain. With many forms of arthritis, the synovial fluid inside the knee is either depleted or reduced. This can lead to joint pain when bones rub against one another. HA is a naturally occurring substance made of cartilage matrix. This solution enhances viscosity of the joint fluid, which improves movement and function. In several meta-analyses, researchers confirmed an overall beneficial effect of hyaluronic acid joint injections.

What are platelet-rich plasma injections?

PRP is prepared from the patient’s own blood, which is put through a laboratory device (centrifuge) to concentrate the platelets. The platelets undergo a process called degranulation, which allows them to release growth factors that repair damaged and injured joints. PRP works by delivering growth factors and other active molecules to the injured site.

These factors help with anti-inflammation, coagulation, bone remodeling, and cartilage repair. Clinical studies have shown that three sets of PRP injections at 21-30 day intervals will lead to significant improvement at 6- and 12-month evaluations. With recent studies, PRP performed better than HA for reduction of pain and symptoms.joint-injrction-848x518

What are stem cell injections?

The fluid inside the joint contains stem cells, which can change into different cell types. However, there is only a small number of stem cells in the joint. A stem cell injection can be given to an injured or damaged joint, which will lead to a self-healing process. Growth factures in stem cells work to repair joint tissues and cartilage.

How is a joint injection performed?

The doctor will often use x-ray guidance (fluoroscopy) to assure correct needle placement. The knee/joint region is cleaned using an antiseptic. After skin is numbed, the procedure needle is inserted. The medication or solution is injected, and the needle is removed. A small bandage will be applied over the area.

How will my joint feel after an injection?

Depending on the solution injected, the joint will usually feel a bit tender for a few hours. With a corticosteroid injection, the medication begins to work after 2-4 days, and improvement is noted after a few weeks. With HA, the solution can cause a day or so of discomfort, but it is mild pain. After a few days, you will notice improved mobility and function. With PRP and stem cell injections, the joint often has a week period of mild discomfort. Peak improvement is noted after 1-2 months.


Avhan E, Kesmezacar H, & Akgun I (2014). Intraarticular injections (corticosteroid, hyaluronic acid, platelet rich plasma) for the knee osteoarthritis. World J Orthop, 5(3), 351-361.