Evolution of Technology

Total Knee Replacement

Total knee replacement surgeries have been performed since the late 1800’s and fortunately technology has continued to advance throughout the history of the procedure. Currently the most common material used for components are various metal alloys to include titanium, cobalt-chrome, and stainless steel as well as high grade plastics known as polymers.

Most systems consist of three parts, the femoral component which caps the endo of the femur, the tibial component which caps the top of the tibia, and the poly (short for polymer component) which rests between the tibial and femoral component and acts as the new cartilage or bearing surface. Many different companies produce components used in total knee replacement and all of the currently used implants have been extensively studied and approved to be safe for use by the Food and Drug Administration.

Regardless of the implant chosen by the surgeon, due to the improvements in technology and material properties throughout the history of total joint procedures, current implants are the best that we have ever had and demonstrate improved wear rates, longer success periods, higher success rates, more anatomic designs, and decreased need for revision surgery due to wear.

Evolution of Procedure

Joint Replacement Surgery

Joint replacement surgery is one of the most commonly performed procedures in all of orthopaedics and has been shown to be one of the most successful with greater than 90-95% of patients experiencing good to excellent results. The goals or surgery are to decrease pain and increase function. To complete this, surgery entails removing the native joint surfaces at the distal femur, proximal tibia, and patella and to replace these surfaces with metal and plastic components which act as the new weightbearing surfaces of the joint and new gliding surfaces, accommodated by the plastic or poly. Typically, the procedure is performed over the course of one to two hours and is performed under either general anesthesia or a spinal anesthetic (such as a spinal or epidural) with lighter sedation. The surgery is performed through a single incision at the front of the knee, with some technique variations like minimally invasive or curved incisions, with the understanding that these variations have no increased benefit compared to a standard approach. If you have previous scars over the knee, these will often be incorporated into your incision. . Patients are encouraged, barring complications, to walk on their new knee the same day as surgery and are typically discharged from the hospital the same day or one day later.

Evolution of Diagnosis

Tri-compartmental (complete) Osteoarthritis of the Knee

Osteoarthritis of the knee is a degenerative condition of the joint which causes progressive loss of articular or joint lining cartilage. The disease process occurs over many years and is typically a result of

natural aging and degeneration over time although it can be accelerated by things such as a history of traumatic injury or ligamentous instability (ie. Chronic ACL tear or fracture). Knee osteoarthritis is very prevalent, occurring in a large percentage of patients over the age of 60 years old, but also becoming common in younger patients with an increase in obesity and activity levels.

Risk factors include older age, female sex, previous injury to the knee, large body mass index and obesity, abnormal cholesterol with high blood pressure and diabetes, and repetive stress to the joint often seen with heavy or manual labor. There are multiple treatment options to attempt to alleviate symptoms of knee pain and loss of function associated with knee arthritis, including anti inflammatories, physical therapy, weight-loss, braces, activity modification and injections into the joint, either steroid or viscosupplementation, or gel injections.

Ultimately, these treatment options simply try and alleviate that pain and decreased function of knee arthritis, and do not cure the underlying cause, which is loss of knee cartilage. TO many, this disease process eventually leads to surgery and total knee replacement as treatment options for pain become unsuccessful or not long lasting. symptoms . To date the only indicated surgery for osteoarthritis affecting the entire knee joint is total knee replacement.