Knee Replacement

Knee Replacement surgery is carried out to provide relief from pain and disability by replacing the weight-bearing surfaces of the knee joint. Knee replacement surgery is mostly carried out to treat osteoarthritis, rheumatoid arthritis, and psoriatic arthritis.

Knee replacement surgery is a frequent and cost-effective musculoskeletal surgical technique. The number of cases done continues to rise across the world, with significant variance in utilization rates among regions and nations.

The most prevalent cause for surgery is painful knee osteoarthritis, which results in diminished function and quality of life. The intervention threshold is not well defined and is influenced by a number of factors, including the patient's and surgeon's preferences.

Although the majority of patients have a very favorable clinical result following a knee replacement, many studies have found that 20% or more of people do not. So, despite the outstanding long-term survivorship, additional effort is needed to improve this method, and research should be focused on boosting the number of patients who have effective pain alleviation following surgery.

Anatomy and Physiology

The knee is a synovial hinge joint that has very little rotational mobility. It is made out of three bones: the distal femur, the proximal tibia, and the patella. There are three distinct articulations and compartments: the medial femorotibial, the lateral femorotibial, and the patellofemoral. The congruity of the joint, as well as the collateral ligaments, offer stability to the knee joint.

The capsule covers the whole joint and extends proximally into the suprapatellar pouch. The femoral condyles, tibial plateaus, trochlear groove, and patellar facets are all covered in articular cartilage. Menisci are interposed in the medial and lateral compartments of the femur and tibia, acting to preserve the articular cartilage and support the knee.

The mechanical axis of the femur is 3 degrees valgus to the vertical axis, as defined by a line drawn from the center of the femoral head to the center of the knee. The anatomic axis of the femur is 6 degrees valgus to the mechanical axis and 9 degrees valgus to the vertical axis, as defined by a line bisecting the femoral shaft.

The proximal tibia is turned 3 degrees varus. The proximal tibia's varus position, along with the offset of the hip center of rotation, results in the tibia's weight-bearing surface being parallel to the ground. The proximal tibia's sagittal alignment slopes posteriorly by 5 to 7 degrees. The asymmetry of normal bone architecture preserves joint alignment and ligamentous tension.

Indications for Knee Replacement Surgery 

Knee replacement is a well-described therapy option for people with osteoarthritic knee discomfort who have failed conservative treatment approaches. It is a reliable technique that relieves pain while also improving the patient's functional condition.

Knee replacement is a well-described therapeutic option for persons with osteoarthritic knee pain who have tried and failed conservative treatment options. It is a dependable treatment for relieving pain and enhancing the patient's functioning state.

Clinical symptoms of osteoarthritis include:

• Knee pain
• Pain with activity and improving with rest
• The pain gradually worsens over time
• Decreased ambulatory capacity

Clinical evaluation includes:

• Full knee exam including a range of motion and ligamentous testing
• Knee radiographs include standing anteroposterior, lateral, 45-degree posteroanterior, and skyline view of the patella

Radiographic evidence of osteoarthritis include:

• Joint space narrowing
• Subchondral sclerosis
• Subchondral cysts
• Osteophyte formation

Conservative treatment includes:

• Non-steroidal anti-inflammatory medication
• Weight loss
• Activity modification
• Bracing
• Physical therapy
• Viscosupplementation
• Intra-articular steroid injection

Contraindications

Absolute

• Active (less than 1 year) knee sepsis
• Presence of active infection elsewhere in the body
• Extensor mechanism dysfunction
• Medically unstable patient

Relative

• Neuropathic joint
• Poor overlying skin condition
• Morbid obesity
• Noncompliance due to major psychiatric disorder, alcohol, or drug abuse
• Insufficient bone stock for reconstruction
• Poor patient motivation or unrealistic expectation
• Severe peripheral vascular disease

Knee Replacement Complications

Potential complications include: 

• Infection
• Blood clot
• Pulmonary embolism
• Fracture
• Dislocation
• Instability
• Osteolysis resulting in component loosening
• Pain
• Stiffness             
• Vascular injury
• Nerve injury

A knee replacement is one option, but you may not require surgery, at least not right immediately. Furthermore, some people are unable to have knee replacement surgery for a variety of reasons. 

Other persons with knee discomfort are too young for a knee replacement since the prosthetic knee is only expected to last 15 or 20 years before requiring revision surgery. There are various things you may try first, either on your own or with the assistance of a specialist, to alleviate knee discomfort and even delay the need for knee replacement.

Knee Replacement Alternatives

Most orthopedic physicians will advise their patients to get knee replacement surgery. They believe that even the greatest knee pain treatments are just temporary. Their patients will eventually require a partial or complete knee replacement.

And, right now, doctors are eager to prescribe surgery due to several innovations that make the treatment less time-consuming and more comfortable for patients. However, if a patient wishes to avoid or postpone surgery, a surgeon would most likely propose the following choices.

1. Weight Loss and Exercise

The best way to avoid knee replacement surgery and reduce knee pain is to lose weight. This can be achieved by eating a healthy diet and doing physical exercise under the guidance of a trainer. The patient should consult a nutritionist to know how to lose weight. For people who are obese, their extra weight puts pressure on the knees and increases stress on the joint. Activities like yoga, cycling, walking, and other physical exercise can be done to reduce weight.

Decreasing weight can assist whether you have arthritis in one or both knees. If you are overweight or obese, speaking with a nutritionist or a bariatric expert may be a good place to start.

Suitable activities include:

• Swimming
• Walking
• Cycling
• Strengthening exercises
• Neuromuscular training
• Water exercise
• Yoga
• Tai chi

2. Physical Therapy

Physical therapy from an experienced physical therapist shows a positive effect on knee pain. Methods like heat and ice, electrical nerve stimulation should be done under the observation of a physical therapist. Moreover, a physical therapist monitors the exercise procedure and helps to increase the strength of the muscles. This in return reduces the pain

Strengthening the quadriceps and hamstring muscles in the leg will help lessen discomfort and make mobility easier. Experts recommend doing low-impact exercises on a routine basis, such as riding a bike or walking on a treadmill.

3. Arthroscopic surgery

Arthroscopic surgery is a small procedure that is less invasive. In order to remove bone fragments or damaged cartilage, as well as to repair ligaments, a surgeon may recommend arthroscopic surgery.

An arthroscope helps a surgeon to see the inside of the joint by doing a small incision. The surgeon uses the arthroscope to work on the inside of the knee after making two to four incisions. Recovery is very quick and people can get discharged on the same day.

4. Knee Osteotomy

Osteotomy (surgical realignment by cutting one or more bones) is favorable in those who have knee deformity in only one side of their knee. This procedure drops down the weight-bearing load, away from the damaged area of the knee. Knee osteotomy is suitable for younger people with limited knee damage.

5. Medication and Steroids

The American Association of Hip and Knee Surgeons advises against utilizing opioid medicines for knee osteoarthritis, except in extremely rare circumstances. Opiate pain medications, in addition to being addictive, have not been shown to be any better than nonsteroidal anti-inflammatory medicines at addressing knee pain in the long run (NSAIDs). 

Though safer than opioids, NSAIDs aren't for everyone, and specialists suggest using them with caution. Even over-the-counter medications such as naproxen and ibuprofen might have negative effects, so consult your doctor.

Unfortunately, these are only short-term fixes. The inflammation will reoccur if the underlying source of the discomfort is not treated. Patients will have to continue taking these drugs (which may have long-term negative effects) or consider other options for knee replacement surgery.

NSAIDs can cause a rise in blood pressure. Larger studies have connected several of these pain medications to an increased risk of heart attack, and the more you take, the more likely you are to experience heartburn, stomach irritation, or even bleeding ulcers.

6. Supplements

Glucosamine sulfate and hyaluronic acid are the two most common supplements used for reducing knee arthritis symptoms. A dietary supplement called glucosamine/chondroitin can enhance the mobility of the joint and minimize pain from knee arthritis. Glucosamine and chondroitin sulfate are naturally occurring molecules in the body. 

7. Intra Articular Injection of Hyaluronic Acid

The intraarticular injection of hyaluronic acid comes under the category of Viscosupplementation. These injections are administered directly into the joints and increase lubrication. This increases mobility and reduces pain. The primary aim of the intraarticular injections is to increase synovial fluid viscoelasticity which reduces friction between the bones. 

Other injectable medicines, such as platelet-rich plasma (PRP) and concentrated bone marrow or stem cells, have less evidence supporting their advantages, according to specialists, but additional research will disclose more about their usefulness in treating knee arthritis.

Knee replacement alternative gel injections have been used for decades and are frequently advised as the first line of defense before a doctor suggests surgical therapy. A 2019 study discovered that newer hyaluronic acid gel monoinjections can be just as effective as older ones that need numerous once-week injections. This is wonderful news since it means fewer trips to the doctor, less money out of pocket, and less discomfort.

Unfortunately, this is frequently only a temporary remedy. If a patient has osteoarthritis, the illness will advance and surgery will eventually be advised by the patient's doctor. NSAIDs and gel injections can be useful. However, they are frequently only short-term fixes.

8. Radiofrequency Ablation

If you do not find relief with any of the above-mentioned alternatives, your physician might suggest the option of Radiofrequency Ablation. Radiofrequency Ablation provides relief from pain in the knees by removing out the sensory nerves that are responsible for transferring pain signals from the knee to the brain. It is, in general, a temporary solution as you may feel pain once the sensory nerves grow back.

9. Bracing

Braces are an excellent option for providing external stability to the knee joint. They are customized to impart enhanced mobility, pain reduction, and joint stability. They are made of metal, leather, and/or plastic and strengthen knee muscles. Bracing allows the realignment of joints and reduces the contact of bones. This helps in improving mobility.

Every patient should consult their physician before carrying out any of the above alternative methods to delay or avoid knee replacement surgery.

10. Cartilage Regeneration

For knees with a limited amount of arthritis and good alignment of the bones, doctors may be able to offer newer treatments that replace cartilage instead of replacing the entire joint. There are several cartilage-regeneration techniques that you may consider and discuss with an orthopedic surgeon.

Autologous chondrocyte implantation (ACI), for example, involves taking a sample of your cartilage cells, growing them in a lab, and then surgically replanting them in your knee. It’s not for everyone, but young people and athletes affected by cartilage loss may be candidates.

What are the Latest Alternatives to Knee Replacement?

Stem Cell Knee Replacement 

The stem cell alternative to knee replacement is an intriguing medical discovery. This sort of treatment, in theory, harnesses the body's inherent healing processes to restore cartilage injury. The objective is to:

• Slow and repair damage
• Reduce pain and inflammation
• Prevent knee replacement surgery

The treatment entails taking blood from the patient, concentrating the stem cells, and injecting the concentrated cells into the knee.

The American College of Rheumatology and the FDA do not currently support this type of therapy. It is classified as "investigational" because there is insufficient evidence to establish that it is safe or effective.

Genicular Artery Embolization (GAE)

One of the reasons for knee discomfort in osteoarthritis patients is abnormal blood vessel creation, commonly known as angiogenesis. Angiogenesis is a critical stage in the beginning and maintenance of joint capsule inflammation. Osteoarthritis is characterized by abnormal arteries that rupture into avascular cartilage in the knee, and it is one of the disease's diagnostic markers.

GAE is an interventional radiology procedure that helps alleviate osteoarthritis pain by addressing the underlying faulty blood vessels. The technique prevents aberrant blood vessels from forming. This decreases inflammation and the discomfort that it causes.

The technique is carried out by an interventional radiologist (IR). An IR is educated and trained to do minimally invasive vascular operations to address a variety of ailments. They treat their patients using angioplasty (widening narrow or obstructed blood arteries to enhance blood flow) and embolization (blocking blood flow from blood vessels).

An interventional radiologist (IR) is a medical specialist who has completed at least six years of specialized training in radiology and interventional radiology.

• Who is a Good Candidate for GAE?

Patients who have tried NSAIDs or knee injections without success or long-term relief might consider genicular artery embolization. It is also appropriate for people who do not want to undergo an invasive surgical treatment or who are not surgical candidates.

Other indications that GAE is a good option for a patient:

• They have moderate-to-severe knee discomfort.
• They are prone to localized soreness.
• An x-ray confirmed the diagnosis of osteoarthritis.
• There are no bone defects in the patient.
• Other conservative therapies have failed to provide beneficial effects for the patient.

Patients with end-stage osteoarthritis, a tumor, an infection, or an inflammatory illness such as rheumatoid arthritis are not excellent candidates.

Orthobiology

Orthobiology is an essential component of new discoveries and cutting-edge technologies in the field of medical research, where professionals and scientists strive every day to enhance the quality of life for many people. Devices, equipment, and products produced by ARTHREX, an orthopedic medical device company with 10 years of expertise in the creation of orthobiological devices, have demonstrated that patients may now enjoy even better treatment outcomes than in the past.

Prolotherapy

Prolotherapy is a treatment for joint and muscular pain. It's also known as regenerative injection treatment or proliferation therapy.

Prolotherapy is injecting a sugar or saline solution into a painful joint or muscle to function as an irritant. It is believed that your body detects the irritant and sends immune cells and other substances to the affected region, so initiating your body's natural healing process. This procedure is intended to aid in the restoration of any injured soft tissue in your joint or muscle region, such as nerves, blood vessels, and muscle tissue.

Methods of treating knee problems with oriental therapy

Traditional Chinese medicine (TCM) is now recognized as a supplemental treatment for knee osteoarthritis. However, the intervention's effectiveness and safety remained contradictory and ambiguous. 

These advantages include pain alleviation, functional improvement, and the absence of a significant number of side events. Meanwhile, the field's methodology and evidence quality were uncertain.

When it’s Ttime for Knee Replacement Surgery?

Knee arthritis might worsen despite therapy. If you've tried these approaches and are still experiencing discomfort, it may be time to consult with an expert orthopedic surgeon about knee replacement. Total knee replacement is a significant treatment, but it can provide long-term benefits in terms of quality of life and mobility.

A total knee replacement is more of a resurfacing of the bones of the knee: the femur (thigh bone), the tibia (the thicker of the two bones in the shin), and the inward-facing surface of the patella, or kneecap.

The bony surfaces are removed and replaced with metal and plastic implants by the surgeon. The plastic performs the same role as the cartilage in that it allows the implants to move smoothly against one other.

The field of knee replacement is constantly evolving. For example, more surgeons are adopting regional anesthetics for the treatment, which might result in a shorter hospital stay as compared to general anesthesia. New multimodal pain methods, surgical procedures, and post-surgery physical therapy are all enhancing patients' knee replacement experiences.

Knee Replacement Recovery Time

Most patients can care for themselves and resume regular daily activities within 6 weeks, and they can drive within 3 to 6 weeks. It might take 4 to 6 months, or perhaps a year, to fully heal and reap the full advantages of knee replacement surgery.

Knee Replacement Cost

According to studies, the overall average cost of a knee replacement in the United States in 2020 will be between $30,000 and $50,000. However, determining what that price tag entails might be difficult.

Conclusion

The number of individuals suffering from knee discomfort caused by osteoarthritis will continue to climb, particularly as life expectancy and obesity rates rise. These two mechanisms lead to articular cartilage wear and tear in the major weight-bearing joints found in primary osteoarthritis.

Secondary osteoarthritis, or osteoarthritis induced by an abnormal concentration of force across the joint, such as in rheumatoid or post-traumatic situations, can also occur in patients. In either scenario, a comprehensive history, physical examination, and suitable radiographs are required for an accurate diagnosis. The first therapy is conservative and involves any and all of the above-mentioned combinations.

When conservative therapy no longer works, surgical intervention may be considered. In the right patient, knee replacement is a dependable surgical operation with a predictable outcome. With 10 to 25 years of follow-up, reported survival rates are as high as 85 percent.

Surgery is sometimes the best option for a patient. Surgery, on the other hand, should be used as a last option if at all feasible. From the general anesthetic pills through the operation itself, every aspect of knee surgery places strain on the body. The body must then recuperate following surgery. Even the healthiest individuals might take up to a year to recover completely.

Often, deferring surgery or eliminating it entirely is the best option. Fortunately, there are now more options to knee replacement surgery than ever before. Before making a treatment decision, patients should explore all of their options with their doctor and seek a second opinion.