Knee injections vs. knee replacement: what are my options?

Knee injections vs. knee replacement: what are my options?

According to the Arthritis Foundation, over 50 million Americans have arthritis. The most common form of arthritis is osteoarthritis, which is a degenerative joint disease. Though it can occur in younger people, it often affects people 50 years of age and older.

Osteoarthritis (OA) is a chronic condition that causes the cartilage between the joints to break down. Cartilage behaves as a cushion for joints and protects the surface of the bones. Without this cushion, bones can rub or grind together, causing pain, stiffness, and swelling.

Doctors may recommend physical therapy, a knee brace or other self-care measures to help with the pain and discomfort of OA. For some individuals, oral medications may also relieve knee pain.

If a patient continues to experience discomfort, swelling, or have extensive joint damage, their doctor may suggest other options. They may require knee injections or even a full knee replacement.

Understanding knee injection therapy

Doctors will typically recommend knee injection therapy before recommending surgery. There is a variety of different injections available. For some people, injections help to alleviate knee pain. The following are knee injection therapy options:

Hyaluronic acid supplements (viscosupplementation)

These are also known as gel injections. During treatment, a substance called hyaluronic acid is injected directly into the knee joint to add to the hyaluronic acid that the body makes naturally.

In healthy joints, this fluid acts as a lubricant or shock absorber, helping the joints to work properly.

People with OA seem to experience a breakdown in hyaluronic acid. Hyaluronic acid injections can help to lessen joint pain as well as inflammation.

A small amount of joint fluid will be removed before the injection to make room for the hyaluronic fluid. Patients receive a weekly injection for 1 to 5 weeks depending on the product used. The supplement is available in solution or gel form.

Doctors will usually recommend injections before surgery to treat long-term knee pain.

Hyaluronic acid supplements can be an effective form of treatment but they do carry some side effects. Common side effects include irritation at the injection site, pain, swelling, stiffness, and fluid buildup around the knee.

Less common side effects include:

  • Bleeding
  • Blistering
  • Burning
  • Rash
  • Itching
  • Skin irritation around the knee
  • Headache
  • Nausea
  • Muscle pain

Patients should be aware of the possible side effects and report these or any other problems to a doctor immediately. It may be necessary to discontinue use or try a different supplement.

Corticosteroid injections

Corticosteroid injections are one of the most common injection options. Doctors inject corticosteroids directly into the knee joint to help relieve knee pain and inflammation quickly.

Corticosteroid injections can be carried out in a doctor's office.

Corticosteroids are a class of medications related to the steroid cortisone. They are routinely used to reduce inflammation. Corticosteroids mimic the effects of a substance called cortisol which is naturally produced by the adrenal glands.

In high doses, corticosteroids can lessen inflammation. They are also beneficial in suppressing the immune system. This can be helpful in controlling conditions such as rheumatoid arthritis where the immune system mistakenly attacks its own tissues.

The corticosteroid is quickly absorbed into the bloodstream and travels to the inflammation site. Injection therapy provides much quicker relief to the inflamed area and is more powerful than traditional oral anti-inflammatory medications.

In addition to providing quick relief, the injection does not cause many of the side effects that oral corticosteroid medications do.

Doctors can administer the injection in their office. They may numb the knee area before injecting the corticosteroid drug directly into the joint. Some people feel relief almost immediately while others only feel the effects several days later.

Depending on the condition of the knee, the benefits can last from a few days to more than 6 months. Factors such as the extent of inflammation and overall health play a role in how long the effects of the steroid injection will last. It is important to note that the effects of the shot are temporary. Additional cortisone injections may be necessary.

Many people have no adverse effects with steroid injections besides a little pain or tingling where the injection was made. In some cases, however, corticosteroids can cause dangerous side effects, especially when taken too often.

Side effects include:

  • Death of nearby bone (osteonecrosis)
  • Joint infection
  • Nerve damage
  • Thinning of the skin and soft tissue around the injection site
  • Temporary flare of pain and inflammation in the joint
  • Thinning of nearby bone (osteoporosis)
  • Whitening or lightening of the skin around the injection site
  • Diabetic patients can experience elevated blood sugar
  • Allergic reaction

Exposure to high levels of cortisol over a prolonged period of time increases the risk of developing hypercortisolism or Cushing's syndrome. Effects include upper body obesity, a round-shaped face, increased bruising, trouble healing, weak bones, excessive hair growth, irregular menstrual periods in women and fertility problems in men.

This side effect is treated by gradually reducing the amount of cortisone used or adjusting dosage.

Is knee replacement my only option?

Though corticosteroid and hyaluronic acid supplements can control pain and inflammation efficiently, they often just provide temporary relief. As OA progresses, mobility and quality of life may get worse, leaving a knee replacement as the only option.

A doctor will likely recommend knee replacement surgery once all other treatment options such as physical therapy and injections have been tried.

A knee replacement is also referred to as knee arthroplasty or knee "resurfacing" because only the surface of the bones is replaced. The surgeon will cut away damaged bone and cartilage from the shinbone and kneecap and replace it with an artificial joint.

During a total knee replacement, the damaged knee joint is removed and replaced with a prosthesis made out of metal, ceramic, or high-grade plastic and polymer components.

There are four basic steps:

  1. Preparing the bone - the cartilage surfaces that are found at the end of the femur and tibia are removed along with a small amount of underlying bone.
  2. Positioning the metal implants - the cartilage and bone that have been removed are then replaced with metal components to recreate the surface of the joint. The metal parts are either cemented or "fit" into the bone.
  3. Resurfacing the patella - the undersurface of the patella or kneecap may be cut and resurfaced with a plastic button.
  4. Inserting a spacer - a medical-grade plastic spacer is inserted between the metal components to create a smooth gliding surface, making walking easier and smoother.

Before the procedure, patients will work alongside with their doctors to design their artificial knee. Factors such as age, weight, activity levels, and overall health are taken into account.

Delaying your surgery

There are risks associated with delaying knee replacement surgery. The main risks are deterioration of the joint, increased pain, and lack of mobility.

Some cases of OA of the knee can only be treated with replacement surgery.

Other risk factors include:

  • Risk of deformities developing inside and outside the joint
  • Risk of muscles, ligaments, and other structures becoming weak and losing function
  • Increased pain or an inability to manage pain
  • Increased disability or lack of mobility
  • Difficulty with normal daily activities

The doctor will thoroughly explain the procedure and allow the patient to ask questions as needed. They will record a medical history, including any medications or supplements that are being taken. Allergies and previous health problems should also be noted.

Patients are typically put to sleep under general anesthesia before the surgery. Patients often begin physical therapy to get the new joint moving during a short hospital stay. Rehabilitation to help regain strength and range of motion continues after leaving the hospital.

Knee replacement risks

Though knee replacement surgery often goes smoothly, it carries risks just like any other surgery.

These risks include:

  • Infection
  • Blood clots in the leg vein or lungs
  • Heart attack
  • Stroke
  • Nerve damage

If surgery is postponed for too long, other risks may arise. Developed deformities may make the knee replacement procedure much more complicated. Surgery may take longer, and knee replacement options may be limited.

Regaining mobility

Both knee therapy and knee replacement are viable treatment options, depending on the severity of joint degeneration.

Physical therapy and oral medications are usually the first treatments that are offered. If oral medication is unsuccessful, injection therapy is often next. For some, injections in conjunction with lifestyle changes such as exercise help to control OA.

Though it may not last forever, a knee replacement is generally the final option when pain and a lack of mobility get too much. Surgery is generally recommended when people have severe knee pain or stiffness that limits their ability to move.

Whether a patient is undergoing injection therapy or a full knee replacement, their doctor can discuss the pros and cons to ensure they make the best decision.

Learn more about the causes of severe knee pain here.

Alternatives to knee replacement - Dr. Prashanth Jain (Video Medical And Professional 2020).

Section Issues On Medicine: Medical practice